Answer:
42
Step-by-step explanation:
Total = 140 Jelly Beans
You are interested in the 3 part of the ratio.
Notice the word total. You should not be using 3/7 at all.
The ratio you want is 3/10. 10 represents the total.
3/10 = x / 140 Cross multiply
10 x = 3 * 140
10x = 420 Divide by 10
10x/10 = 420 / 10
x = 42
Check
How many jelly beans are left?
140 - 42 = 98
Thats the number of Blue Jelly Beans.
Does 42/98 = 3/7?
Yes. Divide top and bottom by 14 and you get 3/7