To find out what percentage 21 is of 42, you can use the formula:
Percentage = (Part / Whole) × 100
In this case, the ‘Part’ is 21 and the ‘Whole’ is 42. Plugging in these numbers, the calculation looks like this:
Percentage = (21 / 42) × 100
When you divide 21 by 42, you get 0.5. Then, multiply that result by 100:
Percentage = 0.5 × 100 = 50
Therefore, 21 is 50% of 42.