7th Grade Challenging Math

733) Answer 31 to 9. Solution
1: In Ed's lemonade, the amount of water is 3/(3 +1) = 3/4 = 15/20 gallons In Alysa's lemonade, the amount of water is 4/(4 +1) = 4/5 = 16/20 gallons When the 2 lemonades are mixed, the total amount of water is 31/20 gallons The total amount of lemon juice is 5/20 + 4/20 = 9/20 gallons Therefore, water to lemon juice ratio is 31 : 9.
Solution 2:
Ed's lemonade is 3/4 water, which is 0.75 of a
gallon of water. Alysa's lemonade is 4/5 water, which is 0.8 of a gallon of
water. When they're mixed together, the amount of water is 1.55 gallons.
Therefore, the amount of lemon juice is 0.45 gallons. That is simplified to a
water to lemon juice ratio of 31:9.
