The correct way to write a number line for word problem.

Question

Emily runs 18 miles per week. Yesterday she ran 5 miles. Today she ran 3 more. How many miles does Emily have left to run?

Answer 1

Set the pointer marker at 18.

She ran 5 miles yesterday, so back it up 5, which puts it at 13.

She ran 3 today, so back it up 3 more, which puts it at 10.

So 18 - 5 - 3 = 13 - 3 = 10.

Note that this is the same as 18 - (5+3) = 18-8 = 10

She has 10 miles to go.