The most important strategy in solving data interpretation questions in the IIFT entrance test is the Approximation technique.
Let’s work with an example one is likely to come across: 1617/1760. Here you should think of approximation, what one will do is reduce the numerator to 1600 and increase the denominator to 1800. And hence the approximate value should be 1600/1800 = 8/9 thus the value being equal to 88.88 %. And if we have two close answers like 89% and 92%, we cannot come to a definite conclusion. Hence we should tune our approximation.
If one changes the value of the numerator (increase or decrease), then an opposite change has to be incorporated in the final value. In our example we have reduced the numerator by 17. Hence we have to increase the final value and the extent of increase in value is computed by 17/1617 which is approximately 1%.
If one changes the value of the denominator (increase or decrease), then a similar change has to incorporated in the final value. In our example we have increased the denominator by 40. Hence we have to increase the final value and the extent of increase in value is computed by 40/1760 which is approximately 2.5%. Hence the final value has to be adjusted by 3.5% which in our case would then turn out to be (approximately ) 92%.