Answers to M$A Exam # 1

 

”20”

“25”

“30”

1

$5.75·(4+5) = $51.75

$5.75·(6+5) = $63.25

$5.75·(4+6) = $57.50

2

20·34 = 680

25·34 = 850

30·34 = 1020

3

x: Blackie, Shady

  30 + 2x

  -------

     3

x: Blackie, Shady

  40 + 2x

  ------- 

     3

x: Blackie, Shady

  50 + 2x

  ------- 

     3

4

25x

30x

30x

5

   4th grade: x

80+90+75+x    245+x

---------  =  -----

    4           4

   4th grade: x

80+70+75+x    225+x

----------- = -----

    4           4

   4th grade: x

80+70+85+x      235+x

-----------  =  ------

       4           4

6

8(2x-3) = 16x - 24

8(2x+3) =  16x + 24

8(2x+5) = 16x + 40

7

$4x

$5x

$6x

8

   x+1,x+2,x+3

   X+1,x+2,x+3

   x+1,x+2,x+3

9

3(x+7) = 3x+21

3(x+5) = 3x+15

3(x+5) = 3x+15

10

$10(x+y)

$12(x+y)

$8(x+y)

11

4·4x = 16x

4·3x = 12 x

4·3x = 12x

12

Joan:x

Elliott: 4x

Joan:x

Elliott: 3x

Joan:x

Elliott: 5x

13

Sally: x

Joan: x+5

Sally: x

Joan: x+3

Sally: x

Joan: x+4

14

Measure(B): b

Measure(A): b-15

Measure(B): b

Measure(A): b-12

Measure(B): b

Measure(A): b-14

15

Width: x

Length: 8+2x

Width: x

Length: 10+2x

Width: x

Length: 9+2x

16

Diana: x

Maria: 3x-8

Diana: x

Maria: 3x-5

Diana: x

Maria: 3x-10

17

Pete: x

Aron: x/2

William: x

Alan: x/2

Joe: x

Alan: x/2

18

Left: x

Right: x

Left: x

Right: x

Left: x

Right: x

19

x: no. of videos

cost: $10 + $4x

x: no. of videos

cost: $12 + $3x

x: no. of videos

cost: $12 + $4x

20

$10 + $4·7 = $ 38

$12 + $3·7 = $ 33

$12 + $4·7 = $ 40

21

Rose: x

Sam: 4x

Together: 5x

Rose: x

Sam: 5x

Together: 6x

Rose: x

Sam: 3x

Together: 4x

22

(5x+3) + 1 = 5x+4

(4x+3) + 1 = 4x+4

(5x+4) + 1 = 5x+5