Anne is 2 times as tall as her sister hence 2 * (her sister's height) = 80cm. Her sister's height = 80cm / 2 = 40cm. Bella is 3 times as tall as Anne hence Bella's height is 3 * 80 cm = 240 cm. The height difference between Bella and Anne's sister = 240 - 40 = 200cm.
This justifies what answer for what question? Q & A:
Anne is 2 times as tall as her sister while Bella is 3 times as tall as Anne. If Anne is 80cm tall, what is the height difference between Bella and Anne's sister?
200