If you have 8 yellow balloons for every 12 blue balloons, then if you have 20 balloons in total, 8 out of 20 of those balloons will be yellow. Then you can set up this ratio.
Then, you can use either cross multiplication or multiply the numerator and denominator by the same number to help solve for x. Personally, I prefer cross multiplication.
Finally, solve for x and if you had 100 balloons, you will have 40 yellow balloons.
Answer: 2x-3=15
2(9)-3=15
18-3=15
Answer: 14
Step-by-step explanation:
Given
Excavation cone measures
height 
Diameter 
Truck can dump
at a time
The volume of a cone is

Putting values

No of trips(N) required to accumulate this much volume is given by

Therefore, 14 trips are necessary to accumulate a cone of volume 
Answer:
1. 96 inches squared
2. h=324
3. 85
Step-by-step explanation:
1. v=lwh
v=8•3•4
v=96
2. 345- 21
h=324
3. 1,012/12
=84.3
hope this helped!