Answer:
Step-by-step explanation:
Let the number = n
Multiply both sides by 8
5n = 80
Divide both sides by 5
n = 80/5
n = 16
The number is 16
2) John's age = x
Ahmad age = x + 3
x + x + 3 = = 63
Combine like terms
2x + 3 = 63
Subtract 3 from both sides
2x = 63-3
2x = 60
Divide both sides by 2
x = 60/2
x = 30
John's age = 30
Ahmad age = 33
3) Bobby's age = x
Ahmad's age = 2x
John's age = 2x - 7
x + 2x + 2x - 7 = 38
5x - 7 = 38
5x = 38 + 7
5x = 45
x = 45/5
x = 9
Bobby's age = x = 9 years
Ahmad's age = 2x = 2*9 = 18 years
John's age = 2x - 7 = 18 - 7 = 11 years
4) Perimeter = 42
x + 5 + x - 2 +x + 5 + x - 2 = 42
x + x +x +x + 5 - 2 + 5 - 2 = 42
4x + 6 = 42
4x = 42 - 6
4x = 36
x = 36/4
x = 9
Length = 9 +5 = 14
Width = 9 - 2 = 7
5) a) Perimeter of garden = p + 3p + 2 + p + 3p + 2
= p + 3p + p +3p + 2 + 2
= 8p + 4
b) 8p + 4 = 76
c) 8p = 76 - 4
8p = 72
p = 72/8
p = 9