Year 8 Interactive Maths - Second Edition

Problem Solving 5

Example 17

The sum of three consecutive numbers is 87.  What are the numbers?

Solution:

Let the smallest number be n.
The word consecutive means one after the other.  So, the next two consecutive numbers after n will be n + 1 and n + 2.

So, the three consecutive numbers are 28, 29 and 30.

Example 18

Use the information given in the following diagram to form an equation and then solve it to find the value of the pronumeral.

Solution: