Charles has 66 blue marbles
The ratio of red to blue marbles is 4 to 3, which means for every 4 red marbles, there are 3 blue marbles.
We know Charles has 88 red marbles. To find the number of blue marbles, we can use the proportion:
(Number of red marbles) / (Number of blue marbles) = (4) / (3)
Since we know the number of red marbles and the ratio, we can solve for the number of blue marbles by multiplying both sides of the equation by the number of blue marbles:
88 / (Number of blue marbles) = 4/3
To find the number of blue marbles, we can cross-multiply and divide:
Number of blue marbles = 88 * 3/4 = 66
I hope this helps :)