Ratios and Unit Rates

Question

Tasha has T books. Aisha has twice as many books as Tasha, and altogether they have 30 books. What proportion can be made to find out how many books Aisha has?

Answer 1

A/2T = (A+T)/30

T=Tasha

A=Aisha

A=2T

A+T=30

The first equation tells us that A=2T. Because they are equal to each other, A/2T= 1.

The second equation tells us that A+T=30. Again, because they are equal to each other, (A+T)/30 = 1.

1=1, therefore:

A/2T = (A+T)/30