Answer:
Step-by-step explanation:
Let x = number of small pizzas
Let y = number of medium pizzas
Let z = number of large pizzas
Total weight of pizza = 9 *16 +8 = 152
Total pizza = 17
Total amount = $153
x + y + z = 17 - equation 1
4x + 6y + 15z = 153 - equation 2
3x + 9y + 14z = 152 - equation 3
from equation 1, x = 17 -y -z - equation *
substitute in both 2 and 3
4(17 -y -z) + 6y + 15z = 153 ---- 1
3(17 -y -z) +9y +14z = 152 --- 2
68 - 4y - 4z +6y + 15z = 153 ----i
51 - 3y - 3z + 9y + 14z = 152 ---ii
2y + 11z = 85 ---1
6y +11z = 101 ----2
equation 2 minus equation 1
4y = 16 => y = 4
substitute y in equation 1
8 + 11z = 85 => 11z = 77 => z = 7
subtitute y as 4 and z as 7 in equation *
x = 17 - 4 -7 => x = 6
So, 6 small pizzas, 4 medium and 7 big pizzas were delivered
