What is the weight of two watermelons and one canteloupe?

Question

3 watermelons and 2 cantaloupe weigh 32 pounds. 4 watermelons and 3 cantaloupes weigh 44 pounds. Assume all watermelons and all canteloupes weigh the same.

Answer 1

3w + 2c = 32

4w + 3c = 44

 

Multiply the 1st equation by 4 and 2nd equation by 3, we get:

 

12w + 8 c = 128

12w + 9 c = 132

             

Subtracting the top equation from the bottom equation, we get: c = 4

 

Substituting c = 4 in any one of the above equations and solving, we get: w = 8

 

Therefore, weight of 2w + 1c = 2(8) + 4 = 20 pounds (Answer)