Express each line as a % of Revenue from operations (= 100). Maria: other income 10%, expenses 70%, net profit 40%. Kala: other income 15%, expenses 60%, net profit 55%.

Basis of a common-size income statement (TN HSC Class-12 Accountancy): every item is shown as a percentage of Revenue from operations, so two firms of different size can be compared on a like-for-like basis.

$\text{\% of a line} = \frac{\text{Amount of the line}}{\text{Revenue from operations}} \times 100$

Common-Size Income Statement for the year ended 31st March 2019