Hi Gays,
if you are preparing for the numerical test for the stage one selection day, take a look at this question.
(1) What speed covers 30 miles for 50 minutes ?
Solution:
Given that you are not allowed calculator during the test how do you calculate the answer to the above question within 20 seconds?
This is how you do it.
speed = distance/ time = 30 divide by 50/60 (convert mins to hours)
now, by the time you divide 50 by 60 and then use the result to divide 30, you have spent a significant amount of time.
but if you do it like this, 30 * 60/50 you have eliminated decimals, and you see that it will be faster to divide 30 by 5 and multiply the result by 6
ans = 36 miles per hour.
N.B 
If you want to divide a number by a fraction, you can multiply that number by the inverse of the fraction as shown above.