In Chad's reading class, all the students are reading the same book. The school bought each student a book at $7 per book. If th

Question

2 years ago

13

In Chad's reading class, all the students are reading the same book. The school bought each student a book at $7 per book. If th

ere are 27 students in Chad's class, which of the following expressions could not be used to calculate the total cost?
a. 7(30) - 7(7)
b. 7(20) + 7(7)
c. 7(30) - 7(3)

Mathematics

2 answers:

Molodets [167] · Answer 1 · 2022-06-18T13:17:50+03:00

Molodets [167]2 years ago

8 0

It would be A. 7(30) - 7(7)

natka813 [3] · Answer 2 · 2022-06-18T14:50:33+03:00

Answer:

a. 7(30) - 7(7)

Step-by-step explanation:

Given,

The total number of students = 27,

∵ Every student gets a book of $ 7,

So, the total cost ( in dollars ) = price of each book × total student

= 7 × 27

= 7(27)

∵ 7(30) - 7(7) = 7(30-7) = 7(23) ≠ 7(27)

7(20) + 7(7) = 7(20+7) = 7(27)

7(30) - 7(3) = 7(30-3) = 7(27)

Hence, option 'a' is correct.