## SSC Constable GD Solved Previous Questions Paper

## Elementary Mathematics

**1.**16 men are able to complete a piece of work in 12 days working 14 hours a day. How long will 28 men, working 12 hours a day, take to complete the work?

**[A]**7 days

**[B]**10 days

**[C]**8 days

**[D]**6 days

**Answer:**C. 8 days

**Explanation:**

M1D1H1 = M2D2H2

Where M = number of Men, D = number of days and H = number of hours

Given,

M1 = 16, D1 = 12, H1 = 14, M2 = 28, H2 = 12 and D2 = ?

D2 = (16 x 12 x 14) / (28 x 12)

= 8 days

Then, 28 men working 12 hours a day, take to complete the work in 8 days.

**2.**A certain sum amounts to Rs. 1725 at 15% per annum at simple interest and Rs. 1800 in the same time at 20% per annum at simple interest. Find the sum.

**[A]**Rs. 1700

**[B]**Rs. 1500

**[C]**Rs. 1650

**[D]**Rs. 1200

**Answer:**B. Rs. 1500

**Explanation:**

Let the principle be Rs. x

If rate of simple interest per annum = 15%, amount = Rs. 1725

And rate of simple interest per annum = 20%, amount = Rs. 1800

Then, 5% of principle = 1800-1725 = Rs. 75

Therefore, 100% priniciple = 75 x 100/5

= 75 x 20

=> Rs. 1500

Then, the principle is Rs. 1500

If rate of simple interest per annum = 15%, amount = Rs. 1725

And rate of simple interest per annum = 20%, amount = Rs. 1800

Then, 5% of principle = 1800-1725 = Rs. 75

Therefore, 100% priniciple = 75 x 100/5

= 75 x 20

=> Rs. 1500

Then, the principle is Rs. 1500

**3.**A dealer marks his goods 20% above cost price and allows a discount of 10% to his customers. His gain percentage is?

**[A]**6%

**[B]**7%

**[C]**8%

**[D]**9%

**Answer:**C. 8%

**Explanation:**

Let the cost price of goods = Rs. 100

A dealer marks his goods 20% above cost price.

Then, the price of goods = 100 + 100 x 20/100

= 100+20

= 120

He gave 10% discount,

then selling price = 120 - 120 x 10/100

= 120 - 12

= Rs. 108

Gain% = 108 - 100

= 8%

Then, his gain % is 8

A dealer marks his goods 20% above cost price.

Then, the price of goods = 100 + 100 x 20/100

= 100+20

= 120

He gave 10% discount,

then selling price = 120 - 120 x 10/100

= 120 - 12

= Rs. 108

Gain% = 108 - 100

= 8%

Then, his gain % is 8

**4.**Raja can do a piece of work in 20 days while Ramesh can finish it in 25 days. Ramesh started working and Raja joined him after 10 days. The whole work is completed in?

**[A]**20 days

**[B]**16 2/3 days

**[C]**15 days

**[D]**18 days

**Answer:**B. 16 2/3 days

**Explanation:**

Raja can do a piece of work = 20 days

Therefore, Raja can do a piece of work in a day = 1/20

Ramesh can do a piece of work = 25 days

Therefore, Ramesh can do a piece of work in a day = 1/25

Raja and Ramesh can do together work in a day = 1/20 + 1/25

=> 9/100

Then, Raja and Ramesh can do together work = 100/9 days

Ramesh can do a work in 10 days = 10/25

Remaining work = 1-10/25

=> 3/5

Then, Raja & Ramesh can do complete remaining work = 100 x 3/5 x 9

=> 20/3

Therefore, the whole work is complete = 10 + 20/3

=> 50/3 days

Therefore, Raja can do a piece of work in a day = 1/20

Ramesh can do a piece of work = 25 days

Therefore, Ramesh can do a piece of work in a day = 1/25

Raja and Ramesh can do together work in a day = 1/20 + 1/25

=> 9/100

Then, Raja and Ramesh can do together work = 100/9 days

Ramesh can do a work in 10 days = 10/25

Remaining work = 1-10/25

=> 3/5

Then, Raja & Ramesh can do complete remaining work = 100 x 3/5 x 9

=> 20/3

Therefore, the whole work is complete = 10 + 20/3

=> 50/3 days

**5.**1008 divided by which single digit number gives a perfect square?

**[A]**7

**[B]**8

**[C]**9

**[D]**4

**Answer:**A. 7

**Explanation:**

Take option (1),

1008 divide by 7 = 1008/7 = 144

144 is a square of 12

Now, take option (2)

1008 divide by 8 = 1008/8 = 126

126 is not a square of any number.

Take option (3)

1008 divide by 9 = 1008/9 = 112

112 is not a square of any number.

Take option (4),

1008 divide by 4 = 1008/4 = 252

252 is not a square of any number.

Hence, the answer is 7

1008 divide by 7 = 1008/7 = 144

144 is a square of 12

Now, take option (2)

1008 divide by 8 = 1008/8 = 126

126 is not a square of any number.

Take option (3)

1008 divide by 9 = 1008/9 = 112

112 is not a square of any number.

Take option (4),

1008 divide by 4 = 1008/4 = 252

252 is not a square of any number.

Hence, the answer is 7

**6.**A right circular cone of height 20 cm and base radius 15 cm is melted and casted into smaller cones of equal sizes of height 5 cm and base radius 1.5 cm. The number of casted cones are?

**[A]**100

**[B]**300

**[C]**150

**[D]**400

**Answer:**D. 400

**Explanation:**

The height of a cone = 20cm and radius of cone = 15 cm

Volume of cone = 1/3(Ï€r

Then, volume = 1/3(Ï€ x 15

=> 1500Ï€ cm

The height of small cone = 5cm

Radius of small cone = 1.5 cm

Volume of small cone = 1/3(5 x 1.5 x 1.5 x Ï€)

=> 3.75Ï€ cm

Then the number of small cones = 1500Ï€ / 3.75Ï€ => 400

Hence the number of casted cones = 400

Volume of cone = 1/3(Ï€r

^{2}h)Then, volume = 1/3(Ï€ x 15

^{2}x 20)=> 1500Ï€ cm

^{3}The height of small cone = 5cm

Radius of small cone = 1.5 cm

Volume of small cone = 1/3(5 x 1.5 x 1.5 x Ï€)

=> 3.75Ï€ cm

^{3}Then the number of small cones = 1500Ï€ / 3.75Ï€ => 400

Hence the number of casted cones = 400

**7.**A student starting from his house walks at a speed of 2 1/2 km/hour and reaches his school 7 minutes late. Next day starting at the same time he increases his speed by 1 km/hour and reaches 6 minutes early. The distance between school and his house is?

**[A]**4 km

**[B]**6 km

**[C]**3 1/2 km

**[D]**1 3/4 km

**Answer:**D. 1 3/4 km

**Explanation:**

Let the distance between school and his house be x km

According to question,

x(5/2) + 6/60 = x(5/2 + 1) - 6/60

2x/5 + 1/10 = 2x/7 - 1/10

(7 * 2x - 5 * 2x)/35 = -2/10

(14x - 10x)/35 = -1/5

4x = -7

x = -7/4

As, distance is never in negative

Hence, x = 7/4

Hence, the distance between the school and house is 1 3/4 km

According to question,

x(5/2) + 6/60 = x(5/2 + 1) - 6/60

2x/5 + 1/10 = 2x/7 - 1/10

(7 * 2x - 5 * 2x)/35 = -2/10

(14x - 10x)/35 = -1/5

4x = -7

x = -7/4

As, distance is never in negative

Hence, x = 7/4

Hence, the distance between the school and house is 1 3/4 km

**8.**The mean proportion of 1.21 and 0.09 is ?

**[A]**3.03

**[B]**0.03

**[C]**0.33

**[D]**3.3

**Answer:**C. 0.33

**9.**The value of √.000441 is equal to ?

**[A]**0.21

**[B]**0.021

**[C]**0.0021

**[D]**0.00021

**Answer:**B. 0.021

**Explanation:**

(0.000441)

=> 0.021

^{1/2}= (0.021 x 0.021)^{1/2}=> 0.021

**10.**A batsman makes a score of 87 runs in the 17th inning and thus increased his average by 3. Find his average after 17th inning.

**[A]**90

**[B]**84

**[C]**39

**[D]**87

**Answer:**C. 39

**Explanation:**

Let the average after 17th innings = x

Then, the average after 16th innings = x-3

According to question,

16(x-3) + 87 = 17x

16x - 48 + 87 = 17x

16x + 39 = 17x

17x - 16x = 39

x = 39

Then, the average after 17th innings is 39

Then, the average after 16th innings = x-3

According to question,

16(x-3) + 87 = 17x

16x - 48 + 87 = 17x

16x + 39 = 17x

17x - 16x = 39

x = 39

Then, the average after 17th innings is 39

**11.**A fruit merchant makes a profit of 25% by selling mangoes at a certain price. If he charges rs. 1 more on each mango, he would gain 50%. At first the price of one mango was?

**[A]**Rs. 6

**[B]**Rs. 4

**[C]**Rs. 7

**[D]**Rs. 5

**Answer:**B. Rs. 4

**Explanation:**

Let the price of a mango = Rs. x

Profit = 25%

Then, the selling price of a mango = 125x / 100

=> 5x / 4

According to question,

150x/100 - 125x/100 = 1

6x/4 = 5x/4 = 1

(6x - 5x)/4 = 1

x/4 = 1

x = 4

Then, the first price of a mango is Rs. 4

Profit = 25%

Then, the selling price of a mango = 125x / 100

=> 5x / 4

According to question,

150x/100 - 125x/100 = 1

6x/4 = 5x/4 = 1

(6x - 5x)/4 = 1

x/4 = 1

x = 4

Then, the first price of a mango is Rs. 4

**12.**A seller increases the cost price of an article by 30% and fixed the marked price as Rs. 286. But during sale he gave 10% discount to the purchaser. Percentage of profit will be?

**[A]**15

**[B]**20

**[C]**17

**[D]**10

**Answer:**C. 17

**Explanation:**

Let the cost price of goods = Rs. 100

A dealer marks his goods 30% above cost price.

Then, the price of goods = 100 + 100 * 30/100

=> 100+30

=> 130

He gave 10% discount,

Then, selling price = 130 - 130 * 10/100

=> 130 - 13

=> Rs. 117

Gain% = 117 - 100

=> 17%

Then, gain% = 17%

A dealer marks his goods 30% above cost price.

Then, the price of goods = 100 + 100 * 30/100

=> 100+30

=> 130

He gave 10% discount,

Then, selling price = 130 - 130 * 10/100

=> 130 - 13

=> Rs. 117

Gain% = 117 - 100

=> 17%

Then, gain% = 17%

**13.**An item was sold for rs. 3600 at 25% discount. Its marked price was?

**[A]**Rs. 4500

**[B]**Rs. 4800

**[C]**Rs. 2700

**[D]**Rs. 2880

**Answer:**B. Rs. 4800

**Explanation:**

The selling price of an item = Rs. 3600

Discount = 25%

Then, the marked price of an item = 3600 x 100(100-25)

=> 3600 x 100/75

=> 3600 x 4/3

=> 1200 x 4

=> Rs. 4800

Then, the marked price of an item = Rs. 4800

Discount = 25%

Then, the marked price of an item = 3600 x 100(100-25)

=> 3600 x 100/75

=> 3600 x 4/3

=> 1200 x 4

=> Rs. 4800

Then, the marked price of an item = Rs. 4800

**14.**If the cost of an article is Rs. P after two successive reductions of 20% and 25%, the original price of an article was?

**[A]**Rs. 4P/5

**[B]**Rs. 3P/5

**[C]**Rs. 5P/3

**[D]**Rs. 5P/4

**Answer:**B. Rs. 3P/5

**Explanation:**

The cost price of an article = Rs. P

Successive reductions = 20% and 25%

Then, successive reduction = 20 + 25 - 20 x 25/100

=> 45 - 5

=> 40%

Then, the original price = P - P x 40/100

=> P -2P/5

=> (5P - 2P)/5

=> Rs. 3P/5

Successive reductions = 20% and 25%

Then, successive reduction = 20 + 25 - 20 x 25/100

=> 45 - 5

=> 40%

Then, the original price = P - P x 40/100

=> P -2P/5

=> (5P - 2P)/5

=> Rs. 3P/5

**15.**A plane can cover 6000 km in 8 hours. If the speed is increased by 250 km/h, then the time taken by the plane to cover 9000 km is?

**[A]**5 hours

**[B]**8 hours

**[C]**6 hours

**[D]**9 hours

**Answer:**D. 9 hours

**Explanation:**

A plane can cover 600 km = 8 hours

Then, the speed of a plane = 6000/8

=> 750 km/hr

If the speed increased by 250 km/hr

Then, the speed of a plane = 750 + 250 = 1000 km/hr

Time taken by plane to cover 9000 km = 9000/1000

=> 9 hrs

Then, the time taken by plane to cover 9000 km is 9 hrs.

Then, the speed of a plane = 6000/8

=> 750 km/hr

If the speed increased by 250 km/hr

Then, the speed of a plane = 750 + 250 = 1000 km/hr

Time taken by plane to cover 9000 km = 9000/1000

=> 9 hrs

Then, the time taken by plane to cover 9000 km is 9 hrs.

**16.**A solid right prism made of iron has cross section of a triangle of sides 5cm, 10cm, 13cm and of height 10cm. If one cubic cm of iron weights 7g, then the weight of the prism is?

**[A]**137.32 gram

**[B]**1100.68 gram

**[C]**1570.8 gram

**[D]**1470.8 gram

**Answer:**No Answer Available, Suggest your answer below!

0 1

**17.**A sum of Rs. 800 becomes Rs. 956 in 3 years at a certain rate of simple interest. If the rate of interest is increased by 4% what amount will the same sum become in 3 years?

**[A]**Rs. 1052

**[B]**Rs. 1042

**[C]**Rs. 1024

**[D]**Rs. 1025

**Answer:**A. Rs. 1052

**Explanation:**

A sum of Rs. 800 becomes Rs. 956 in 3 years at a certain rate of simple interest.

Then, the simple interest of three years = 956-800 => 156 Rs.

Simple Interest = (P x t x r)/100

Then,

156 = (800 x 3 x r)/100

r = 156/3 * 8

r = 6.5%

If rate of interest is increased by 4%

Then, the rate of interest = 6.5+4 = 10.5%

Now, simple interest = 800 x 10.5 x 3 /100

=> 24 x 10.5

=> Rs. 252

Then, the amount will be in 3 years = 800 + 252 => 1052

Then, the simple interest of three years = 956-800 => 156 Rs.

Simple Interest = (P x t x r)/100

Then,

156 = (800 x 3 x r)/100

r = 156/3 * 8

r = 6.5%

If rate of interest is increased by 4%

Then, the rate of interest = 6.5+4 = 10.5%

Now, simple interest = 800 x 10.5 x 3 /100

=> 24 x 10.5

=> Rs. 252

Then, the amount will be in 3 years = 800 + 252 => 1052

**18.**A shopkeeper in order to clear his old stock of T.V sets, offer 12% discount on the T.V. sets. If the marked price of a T.V. set is Rs. 6500, the selling price of the T.V. set is?

**[A]**Rs. 5700

**[B]**Rs. 6000

**[C]**Rs. 5720

**[D]**Rs. 5400

**Answer:**C. Rs. 5720

**Explanation:**

The marked price of a T.V set = Rs. 6500

Discount = 12%

Then, selling price of a T.V. set = 6500 x (100-12)/100

=> 6500 x 88/100

=> 65 x 88

=> Rs. 5720

Then, the selling price of a T.V. set is Rs. 5720

Discount = 12%

Then, selling price of a T.V. set = 6500 x (100-12)/100

=> 6500 x 88/100

=> 65 x 88

=> Rs. 5720

Then, the selling price of a T.V. set is Rs. 5720

**19.**Average income of 'A' and 'B' is Rs. 200 and average income of 'C' and 'D' is Rs. 250. The average income of A,B,C and D is?

**[A]**Rs. 200

**[B]**Rs. 225

**[C]**Rs. 125

**[D]**Rs. 106.25

**Answer:**B. Rs. 225

**Explanation:**

The average income of 'A' and 'B' = Rs. 200

Then, the total income of 'A' and 'B' = 2 x 200 => Rs. 400

The average of C and D = Rs. 250

Then the total income of C and D = 2 x 250 => Rs. 500

The total income of A, B, C and D = 400+500 = Rs. 900

The, the average income of A,B,C and D = 900/4 = Rs. 225

Then, the total income of 'A' and 'B' = 2 x 200 => Rs. 400

The average of C and D = Rs. 250

Then the total income of C and D = 2 x 250 => Rs. 500

The total income of A, B, C and D = 400+500 = Rs. 900

The, the average income of A,B,C and D = 900/4 = Rs. 225

**20.**The average of 1,3,5,7,9,11,..... 25 terms is ?

**[A]**125

**[B]**25

**[C]**625

**[D]**50

**Answer:**B. 25

**Explanation:**

The sum of first n odd natural numbers = n

Here n = 25

Then, the sum of 25 odd natural number = 25

Then, the average of 25 odd terms = 625/25 => 25

^{2}Here n = 25

Then, the sum of 25 odd natural number = 25

^{2}=> 625Then, the average of 25 odd terms = 625/25 => 25

**21.**The ratio of ages of two persons is 5:9 and the age of one of them is greater than the other by 40 years. The sum of their ages in years is?

**[A]**140

**[B]**180

**[C]**150

**[D]**150

**Answer:**A. 140

**Explanation:**

The ratio of ages of two persons = 5:9

Let the age of first person be = 5x

The age of second person = 9x

The age of one of them is greater than the other by 40 years

Then, 9x - 5x = 40

=> 4x = 40

=> x = 40/4

=> x = 10

Then, age of first person = 5x10 = 50

age of second person = 9x10 = 90

So, the sum of their ages = 90+50 = 140

Let the age of first person be = 5x

The age of second person = 9x

The age of one of them is greater than the other by 40 years

Then, 9x - 5x = 40

=> 4x = 40

=> x = 40/4

=> x = 10

Then, age of first person = 5x10 = 50

age of second person = 9x10 = 90

So, the sum of their ages = 90+50 = 140

**22.**Study the data and answer the questions

The score of students of a class are given as follows.

The number of students whose IQ score is 100 and more is?

**[A]**36

**[B]**29

**[C]**46

**[D]**35

**Answer:**D. 35

**Explanation:**

The total number of students whose IQ score is 100 and more = 16+13+4+2 = 35

**23.**Study the data and answer the questions

The score of students of a class are given as follows.

Number of students whose IQ score is 140 is?

**[A]**1

**[B]**2

**[C]**0

**[D]**underterminable form

**Answer:**D. underterminable form

**24.**The smallest number by which 243000 be divided so that the quotient is a perfect cube is?

**[A]**9

**[B]**27

**[C]**3

**[D]**1

**Answer:**A. 9

**Explanation:**

Number = 243000

If we divide by 9

Then, 243000/9 = 27000

27000 is a cube of 30

Then, the smallest number is 9 which can divide 243000 so that the quotient is a perfect cube of 30

If we divide by 9

Then, 243000/9 = 27000

27000 is a cube of 30

Then, the smallest number is 9 which can divide 243000 so that the quotient is a perfect cube of 30

**25.**In a college election, a candidate secured 62% of the votes and is elected by a margin of 144 votes. The total number of votes polled is?

**[A]**800

**[B]**925

**[C]**1200

**[D]**600

**Answer:**D. 600

**Explanation:**

Let the total number of votes polled = x

In college election, a candidate secured 62% of the votes

Then, the opposite candidate secured votes = 100-62 = 38%

Candidates elected by 144 votes

Then x * (62-38)/100 = 144

x* 24/100 = 144

x= 600

In college election, a candidate secured 62% of the votes

Then, the opposite candidate secured votes = 100-62 = 38%

Candidates elected by 144 votes

Then x * (62-38)/100 = 144

x* 24/100 = 144

x= 600

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