# Arithmetic sum for RRB PO/Clerk and RBI assistant mains

**1. Efficiency of A is 80% of that of B and efficiency of C is 20% more than that of B. B alone can complete a piece of work in 12 days and received Rs.600 for completing the work. If all 3 started working together on same work, then find the difference in wages received by A & C.**

1. Rs.80

2. Rs.50

3. Rs.100

4. Rs.60

5. Rs.90

2.

**A vessel contains 100 liters milk. 20 liters milk is taken out from the vessel and completely replaced with water and then X liters of mixture is taken out from the vessel and completely replaced with water. If ratio of milk to water in the final mixture is 14 : 11, then find X.**1. 50

2. 20

3. 40

4. 30

5. 60

3.

**Ratio of volume of cylinder to that of cone is 10:3 and ratio of radius of cylinder to that of cone is 2 : 3 and ratio of radius to height of cylinder is 2 : 5. If height of cone is 14 cm, then find curved surface area of cylinder.**1. 2720 cm²

2. 3080 cm²

3. 3140 cm²

4. 3580 cm²

5. 2920 cm²

4.

**75% of A is equal to 40% of C and 80% of B is equal to 100% of A. If sum of 50% of B and 30% of C is equal to 95, then find 80% of A.**1. 72

2. 120

3. 80

4. 64

5. 96

5. A person completes his journey of 2430 km by three mediums . Ratio of the speeds of train, car and bike are 5:3:2 and times of journey are in the ratio 4:3:2.If his final average speed is 30km/hr then what is the difference between the distance covered by train and car ?

A) 680kmB) 720km

C) 810km

D) 850km

E) None of these

6. P and Q can complete a piece of work in 15 days and 12 days respectively. Q starts the work with R . After 2 days ,P joined R on the place of Q and the work got completed by them after 5 days from starting . How many days are required for R to complete the whole work alone?

A) 8(7/19)B) 17(7/19)

C) 19(7/17)

D) 7(17/19)

E) 17(8/17)

7. In a mixture ,ratio of water and milk is 4:5. In the other mixture ratio of milk and water is 3:2. If both mixtures are added in the ratio of 63:55,then what is the ratio of water to milk in final mixture ?

A) 21:30B) 12: 18

C) 25:34

D) 28:36

E) 23:32

8. A train is moving with a uniform speed . It crosses a 400 m long platform in 40 sec and a 800 m long bridge in 60sec. Other train is moving with a uniform speed of 72km/hr and crosses a person standing on platform in 15 sec. What is the ratio of the length of first train to second train ?

A) 4:3B) 5:6

C) 3:2

D) 9:5

E) 5:4

9. In a city ,number of males and females are in a certain ratio, 45% of male population and 35 % of female population are minors who can’t vote .Number of male voters are equal to number of female voters .Number of voters is how much percent of the population of the city ?

A) 60%B) 58.49%

C) 59.58%

D) 55.8%

E) 64.5%

10. The speed of Rajdhani Express and Shatabdi Express are in the ratio 9:11 . They are going in opposite direction along parallel tracks. If each takes 7 seconds to cross a telegraph post ,then how much time taken by the both trains to cross each other completely ?

A) 11 seconds

B) 14 seconds

C) 9 seconds

D) 7 seconds

E) 10 seconds

Average speed = 30km

Total time = 2430/30 81hrs

Time for train =81* (4/9)= 36 hrs

Time for car = 81 * (3/9) = 27 hrs

Time for bike = 81 * (2/9) = 18 hrs

Let speed of the train ,car and bike are 5x , 3x and 2x respectively .

Now ,

5x * 36 + 3x * 27 + 2x * 18 = 2430

=> x = 2430/297 = 90/11

Distance of train = 5 * (90/11) * 36 = 16200/11

Distance of car = 3 * (90/11) * 27 = 7290/11

Required Difference = 16200/11 – 7290/11 = 8910/11 = 810

Now B worked for 2 days and C worked for 5 days . A can complete the work in 15 days . so,work completed by A in 3 days = 3 * (1/15 ) = 1/5

B can completed the work in 12 days . So work completed by Bb in 2 days = 2* (1/12) = 1/6

Work completed by c in 5 days = 5* (1/x) = 5 /x

Now , 1/5 + 1/6 + 5 /x = 1

5 /x = 1 – 11 /30 = 19 /30

=> x = 150/19 = 7.89 = 7(17/19)days

Water in the first mixture = 63 * (4/9) = 28 litres

Water in the second mixture = 55 * (2/5) = 22 litres

Total mixture = 63 + 55 = 118 litres

Total water = 28 + 22 = 50 litres

Total milk = 118 – 50 = 68 litres

Required ratio = 50 :68 = 25: 34

A) 11 seconds

B) 14 seconds

C) 9 seconds

D) 7 seconds

E) 10 seconds

Solution -

Q1. Ans(1)

2. Ans(4)

3. Ans(2)

4. Ans(4)

5.

**Option C****Solution:**

**Total distance = 2430 km**

Average speed = 30km

Total time = 2430/30 81hrs

Time for train =81* (4/9)= 36 hrs

Time for car = 81 * (3/9) = 27 hrs

Time for bike = 81 * (2/9) = 18 hrs

Let speed of the train ,car and bike are 5x , 3x and 2x respectively .

Now ,

5x * 36 + 3x * 27 + 2x * 18 = 2430

=> x = 2430/297 = 90/11

Distance of train = 5 * (90/11) * 36 = 16200/11

Distance of car = 3 * (90/11) * 27 = 7290/11

Required Difference = 16200/11 – 7290/11 = 8910/11 = 810

**km**

6.

**Option D**

**Solution:**

**Let C can complete the whole work alone in x days .**

Now B worked for 2 days and C worked for 5 days . A can complete the work in 15 days . so,work completed by A in 3 days = 3 * (1/15 ) = 1/5

B can completed the work in 12 days . So work completed by Bb in 2 days = 2* (1/12) = 1/6

Work completed by c in 5 days = 5* (1/x) = 5 /x

Now , 1/5 + 1/6 + 5 /x = 1

5 /x = 1 – 11 /30 = 19 /30

=> x = 150/19 = 7.89 = 7(17/19)days

7.

**Option C****Solution:****Let volume of first and second mixtures are 63 litres and 55 litres resp.**

Water in the first mixture = 63 * (4/9) = 28 litres

Water in the second mixture = 55 * (2/5) = 22 litres

Total mixture = 63 + 55 = 118 litres

Total water = 28 + 22 = 50 litres

Total milk = 118 – 50 = 68 litres

Required ratio = 50 :68 = 25: 34

8.

**Option A****Solution:**

**Let the length of first train is x metre .**

Then,

x+400/40 = x+800/60

=> 3x + 1200 = 2x +1600

=> x = 400m

Speed of the second train = 72 * 5 /18 = 20 m/s

Length of second train = 20 * 15 = 300 m

Required ratio = 400 : 300 = 4 : 3

9.

**Option C****Solution:**

**Number of males * 55/100 = Number of females * 65 /100**

Number of males /Number of females = 65 :55 = 13 : 11

Let male population and female population are 13x and 11x resp.

Total population = 13x + 11x = 24x

Number of male voters = 13x * 55 / 100 = 7.15x

Number of female voters = 7.15x

Total voters = 7.15x * 2 = 14.30x

Required % = 14.30x *100/24x = 59.58%

10.

**Option D****Solution:**

**Time to cross each other = (7 * 9 + 7 *11 )/ (9+11) = (63 + 77 )/20 = 7 seconds**