Respuesta :

Answer:

Step-by-step explanation:

10)a) Let the number = x

4x + 8 = 16

Subtract 8 form both sides

4x + 8 - 8 = 16 - 8

4x = 8

Divide both sides by 4

4x/4 = 8/4

x = 2

The number is 2

b) Let the number = x

4x - 8 = 6

Add 8 to both sides

4x - 8 + 8 = 6 + 8

4x = 14

Divide both sides by 4

4x/4 = 14/4

x = 3.5

The number is 3.5

11) a) Increase in cost = 105 - 100 = $ 5

b) Percentage increase = [tex]\frac{5}{100}*100[/tex]

                                       = 5%

12)  Number of girls = 35

Number of girls wearing glasses  = 15

Number of boys = 40

Number of boys wearing glasses  = 10

a) Percentage of boys wearing glasses = [tex]\frac{10}{40}*100\\[/tex]

                                                                 = 25%

b) Percentage of girls wearing glasses = [tex]\frac{15}{35}*100[/tex]

                                                                 = 42.86%

c) Total children = 35 +40 = 75

Total children wearing glasses = 15 + 10 = 25

Percentage of children wearing glasses = [tex]\frac{25}{75}*100[/tex]

                                                                        = 33.33%