Question

Please help!

1. Which expression replaces the blank to form a equation. 30 ÷ 2 + 2 x 7 = blank
A. 3(10 ÷ 2) + 2 x 7
B. 30 ÷ (6+ 2) x 7
C. 3(10) ÷ (2 +2) x 7
D. (5+2) x 7

2. Which value of x makes the open sentence 4 = 10x true?
A. 0.4
B. 2.5
C. 4
D. 25

3. Simplify : | - 7.5 | - |10.3|
A. -17.8
b. -2.8
C. 2.8
D. 8.2

4. Twelve less than the product of a number and 6 is 60. Which equation models the sentence?
A. 12 - n x 6 = 60
B. n ÷ 6 + 12 = 60
C. n x 6 - 12 = 60
D. n ÷ 6 - 12 = 60

Answer 1

1. A. 3(10÷2) +2·7
2. A. 0.4
3. B. -2.8
4. C. n·6 - 12 = 60

Explanation:

1. The given expression evaluates to ...

30÷2 + 2·7 = 15 + 14 = 29

The offered choices evaluate to ...

A: 3(10÷2) + 2·7 = 3·5 + 2·7 = 15 + 14 = 29 . . . . . this will make it true

B: 30÷(6+2)·7 = (30/8)·7 = 210/8 = 26 1/4 . . . . . . ≠ 29

C: 3(10)÷(2+2)·7 = 30/4·7 = 210/4 = 52 1/2 . . . . . ≠ 29

D: (5+2)·7 = 7·7 = 49 . . . . . . . . . . . . . . . . . . . . . . . ≠ 29

2. You can divide the equation by 10 to find the appropriate value of x.

4/10 = 10x/10 = x . . . . . 4/10 matches choice A

3. The expression simplifies to ...

7.5 -10.3 = -2.8 . . . . . . matches choice B

4. "The product of a number and 6" is n×6. Twelve less is n×6 - 12. When that "is 60", the equation can be written ...

n×6 - 12 = 60 . . . . . . . . matches selection C