Answer
Find out the how many plain hamburgers will Jim and his dad make .
To proof
As given
Jim is helping his dad cook hamburgers for his family and friends.
There are 15 people. Each person wants two hamburgers
Total number of hamburgers = 15× 2
= 30
As given
Three people want hamburgers with cheese.
Each person wants two hamburgers
Total hamburgers with cheese = 2 × 3
= 6
As given
Two people want hamburgers with mustard.
Each person wants two hamburgers
Total hamburgers with mustard = 2× 2
= 4
As given
Two people want hamburgers with catsup.
Each person wants two hamburgers
Total hamburgers with catsup = 2 × 2
= 4
As given
The rest want them plain.
let us assume that the plane hamburgers be x .
than the equation becomes
x +6 +4 + 4 = 30
x = 30 - 14
x = 16
Therefore the plain hamburgers will Jim and his dad make be 16 .
Option (b) is correct .
Hence proved
