Question

The ratio of blue marbles to white marbles in a bag is 4 to 5. At this rate, how many blue marbles are there if there are 15 white marbles?

Answer 1

By ratio we have 12 blue marbles for 15 white ones

Explanation:

`("blue")/("white") ->4/5`

Multiply by 1 but where `1=3/3` giving

`("blue")/("white") ->4/5-=[4/5xx1]=[4/5xx3/3]=12/15`

By ratio we have 12 blue marbles for 15 white ones