please answer this.....

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%