The bar chart given below shows the ratio of expenditure to revenue for seven consecutive years Y1, Y2, Y3, Y4, Y5, Y6 and Y7.

The profit percentage is lowest for which year?

We know that profit = Revenue - Expenditure
Expenditure : Revenue for Y1 = 0.8 = $$\dfrac{80}{100}$$
Let Expenditure = 80x, Revenue = 100x
Then, Profit = 100x-80x = 20x
Profit percentage = $$\dfrac{20x}{100x}\times100 = 20$$%
For Y2,
Profit percentage = $$\dfrac{100-75}{100}\times100 = 25$$%
For Y3,
Profit percentage = $$\dfrac{100-84}{100}\times100 = 16$$%
For Y4,
Profit percentage = $$\dfrac{100-90}{100}\times100 = 10$$%
For Y5,
Profit percentage = $$\dfrac{100-70}{100}\times100 = 30$$%
For Y6,
Profit percentage = $$\dfrac{100-75}{100}\times100 = 25$$%
For Y7,
Profit percentage = $$\dfrac{100-96}{100}\times100 = 4$$%
Hence, The profit percentage is the lowest for Y7