Zahra spent $20.50 on 10 party favors for her party. The boys each received a puzzle book that cost $1.75 each. The girls each received a magic trick that cost $2.25 each. How many boys and how many girls attended the party? None of the other answers are correct 4 boys and 6 girls 5 boys and 5 girls 6 boys and 4 girls 7 boys and 3 girls

Respuesta :

x = # of boys, y = # of girls
x + y = 10 --> y = 10-x
2.25y + 1.75x = 20.50
2.25(10-x) + 1.75x = 20.5
22.5 - 2.25x + 1.75x = 20.5
-0.5x = 20.5-22.5
-0.5x = -2.0
÷ -.5 ÷ -.5
x = 4 --> 4 boys, so 10-4 = 6 girls