Question

The cost of a pearl $C is directly proportional to the square of its mass , m grams. given that a pearl of mass 10g cost $240

find the cost of a pearl of mass 25g​

Answer 1

Explanation:

doing with the ratio method

25 x

10 240

x=25×240÷10

Answer 2

It cost $600


10gx2=480
+5g= 120
480+120=600