If A is x% of y and B is y% of x, then

The correct answer is Option (4) → A is equal to B.

“x% of y” means \(\frac{x}{100}\times y\), and multiplication can be done in either order, so x% of y is always the same as y% of x.

• \(\displaystyle A=\frac{x}{100}\times y=\frac{xy}{100}\)

• \(\displaystyle B=\frac{y}{100}\times x=\frac{xy}{100}\)

• So \(A=B\)

Tip: This swap often saves work: 8% of 50 is the same as 50% of 8, that is, 4.