1. Udit can complete his work in 10 days. What amount of work will be completed in 8 days?

2. A train 150m long is running at a speed of 72 km/hr. It crosses a bridge in 13 seconds. Find the length of the bridge

3. If x and y vary inversely and x = 25, when y = 3. Find y, when x =15 (explain with the whole process)

1>Udit takes 10 days to complete a work.

So applying the Unitary method in order to get the solution.


2>Let the length of the bridge be x.

So the speed of the train in m/s is 20 m/s.

Therefore a total of x+150 m is travelled by train in 13 sec.

So,


3>Since x and y vary inversly. So,

So find the value of k we have when x=25, y=3

So,

k=75.

Therefore the equation is

xy=75

So , for x =15,

y= 75/15

 =5

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