Remark
If you are given the total number of laps they swam, then you must compare Ron to the total of the two parts of their ratios.
Solution
The total part of their ratios is 2 + 3 = 5
The proportion looks like this
2 (Ron) / 5 (Total) = x / 70
2/5 =x / 70 Multiply both sides of the proportion by 70
(2/5) * 70 = x
140 / 5 = x
28 = x
Answer
Ron swam 28 laps
C
