# Solving Addition and Subtraction Equations Worksheet

Solving Addition and Subtraction Equations Worksheet
• Page 1
1.
Some years back Carol was traveling by a cargo ship from New Zealand to Tahiti. She was curious to look around the ship one day, and in the boiler room she asked a man how old the ship was. He smiled and replied 'The ship is twice as old as the boiler now. And the combined age of the ship and the boiler is thirty years.' What is the age of the ship and of the boiler?
 a. 15, 15 b. 20, 10 c. 10, 20 d. 25, 5

#### Solution:

Let the present age of the boiler be x.

Then present age of the ship is 2x.
[According to the data.]

Sum of their ages is 30. So, x + 2x = 30 years.
[According to the data.]

3x = 30
[Simplify.]

x = 10

Therefore, the age of the boiler is 10 years and that of the ship is 2x = 2(10) = 20 years.

2.
Which of the following is a solution of the equation $x$ - 36 = 18?

 a. 55 b. 64 c. 18 d. 54

#### Solution:

x - 36 = 18
[Original equation.]

x - 36 + 36 = 18 + 36

x = 54
[Simplify.]

So, 54 is the solution of the equation.

3.
What is the value of the variable $p$ in the equation $p$ - (- 3) = - 2?
 a. - 4 b. - 7 c. - 6 d. - 5

#### Solution:

p - (- 3) = - 2
[Original equation.]

p + 3 = - 2
[Use subtraction rule to simplify.]

p + 3 - 3 = - 2 - 3
[Subtract 3 from each side.]

p = - 5
[Simplify.]

The value of the variable p in the equation is -5.

4.
A lighthouse is constructed on the roof of a 144 ft tall building. The lightning rod attracts lightning through a cable to a point 25 ft under ground. What is the length of the cable?
 a. 169 ft b. 189 ft c. 179 ft d. 159 ft

#### Solution:

Let l be the length of the cable.

l - 25 = 144
[Write the data in the form of an equation.]

l - 25 +25 = 144 + 25

l = 169
[Simplify.]

The length of the cable, l is 169 ft.

5.
The temperature in Dugway is estimated to be 302o K. What is the equivalent temperature in Celsius scale, if K = C + 273?
 a. 575o C b. 129o C c. 29o C d. -29o C

#### Solution:

K = C + 273
[Original equation.]

302 = C + 273
[Substitute 302 for K.]

302 - 273 = C + 273 - 273
[Subtract 273 from each side.]

C = 29o
[Simplify.]

The equivalent temperature of 302o K on the Celsius scale is 29o.

6.
Nina solved the equation $m$ + 4 = 8. If her solution was correct, then which of the following was her solution?
 a. 3 b. 7 c. 5 d. 4

#### Solution:

m + 4 = 8
[Original equation.]

m + 4 - 4 = 8 - 4
[Subtract 4 from each side.]

m = 4
[Combine like terms.]

So, Nina's solution was 4.

7.
Solve the equation $a$ + 44 = 65.

 a. $a$ = 21 b. $a$ = 31 c. $a$ = 26 d. $a$ = 16

#### Solution:

a + 44 = 65
[Original equation.]

a + 44 - 44 = 65 - 44
[Subtract 44 from each side.]

a = 21
[Simplify.]

8.
Solve the equation $p$ - 10 = 32 for $p$.
 a. 42 b. 30 c. 48 d. 36

#### Solution:

p - 10 = 32
[Original equation.]

p - 10 + 10 = 32 + 10

p = 42
[Simplify.]

9.
Solve: 300 = $R$ - 300
 a. 580 b. 560 c. 600 d. 640

#### Solution:

300 = R - 300
[Original equation.]

300 + 300 = R - 300 + 300

R = 600
[Simplify.]

10.
Solve for $x$ in the equation $x$ + 27 = 96.
 a. 64 b. 69 c. 74 d. 77

#### Solution:

x + 27 = 96
[Original equation.]

x + 27 - 27 = 96 - 27
[Subtract 27 from each side.]

x = 69
[Simplify.]