Answer:
The ratio of red pens to pencils is 7/10
The ratio of pencils to red pens is 10/7
Explanation:
Ratio:
The ratio of a to b is a/b
The ratio of b to a is b/a
In this question:
7 red pens
10 pencils
The ratio of red pens to pencils is 7/10
The ratio of pencils to red pens is 10/7