Human Calculator

A train can travel 50% faster than a car. Both start from point A at the

same time and reach point B 75 kms away from A at the same time. On the

way, however, the train lost about 12.5 minutes while stopping at the stations.

The speed of the car is:

• 100kmph

• 110kmph

• 120kmph

• 130kmph

Given that sin(α) = 1/3 and cos(β) = 3/5, find the value of sin(α + β).

• (3 + 8√2)/15

• (2 + 4√2)/15

• (3 + 8√2)/14

• (3 + 8

  √2)/12

A cistern of capacity 8000 litres measures externally 3.3 m by 2.6 m by

1.1 m and its walls are 5 cm thick. The thickness of the bottom is:

• 90cm

• 1m

• 10cm

• 1.1cm

Two trains running in opposite directions cross a man standing on the

platform in 27 seconds and 17 seconds respectively. If they cross each other

in 23 seconds, what is the ratio of their speeds?

• Insufficient data

• 3:1

• 1:3

• 3:2

Find the derivative of the function f(x) = (2x^2 + 3x + 1)(4x^3 - 2x + 5).

• 40x^4 + 68x^3 + 72x^2 - 8x + 46

• 40x^4 + 68x^3 + 72x - 8x^(1/2) + 36

• 40x^4 + 68x^3 + 72x^2 - 8x

• 40x^4 + 68x^3 + 72x^2 - 46

A car travels a distance of 240 kilometers in 4 hours. What is the

average speed of the car?

• 60 km/h

• 80 km/h

• 120 km/h

• 240 km/h

A train travels a distance of 540 kilometers at an average speed

of 90 km/h. If the train stops for 15 minutes during the journey, what is the

total time taken by the train to complete the trip?

• 6 hours

• 6.5 hours

• 7 hours

• 7.5 hours

Find the derivative of the function f(x) = 5x^3 - 2x^2 + 4x - 3.

• f'(x) = 15x^2 - 4x + 4

• f'(x) = 15x^2 - 4x - 4

• f'(x) = 15x^2 - 2x + 4

• f'(x) = 15x^2 - 2x - 4

A car travels a distance of 300 kilometers at an average speed of

60 km/h. How long does it take for the car to complete the journey?

• 2 hours

• 3 hours

• 4 hours

• 5 hours

A bag contains 5 red balls and 7 blue balls. If two balls are

drawn randomly without replacement, what is the probability that both balls

are red?

• 5/66

• 5/33

• 5/12

• 4/11