Find the percent of fruit juice in the 300 liters punch.

Question

200 liters of a punch that contains 35% fruit juice is mixed with 300 liters of another punch. The resulting fruit punch is 20% fruit juice.

Answer 1

let P = percentage of unknown juice

 

then 200L x 35% + 300L x P% = 500L X 20%

 

7000L% + 300LP% = 10000L%

 

 300LP% = 10000L% - 7000L%, which becomes 300LP% = 3000L%

 

solving, P = 3000L% ÷ 300L, so P = 10%