Math Word Problems Demystified - A Self Teaching Guide

SOLUTION:

GOAL: You are being asked to find how much longer Lake Erie is than Lake

Huron.

STRATEGY: Since you are being asked ‘‘how much longer’’ and both items

are the same (miles), you use subtraction.

IMPLEMENTATION: 241 miles
206 miles¼35 miles. Hence, Lake Erie is

35 miles longer than Lake Huron.

EVALUATION: You can check the solution by adding: 206þ 35 ¼241.

Usemultiplicationwhen you are being asked to find

the product,

the total,

how many in all,

how many altogether, etc.,

and you have so many groups of individual items.

EXAMPLE:Find the total number of seats in an auditorium if there are 22

rows with 36 seats in a row.

SOLUTION:

GOAL: You are being asked to find thetotal number of seats in the

auditorium.

STRATEGY: Use multiplication because you are asked to find a total and

you have 22 rows (groups) of seats with 36 (individual items) in a row.

IMPLEMENTATION: 36 22 ¼792 seats. Hence, the auditorium has 792

seats.

EVALUATION: You can check your answer by estimation: 40 20 ¼800.

Since 792 is close to 800, your answer is probably correct.

Usedivisionwhen you are given the total number of items and a number of

groups and need to find how many items in each group or when you are given

the total number of items and the number of items in each group and need to

find how many groups.

8 LESSON 2 Using Whole Numbers