Answer Word Problems Involving Fractions

In this activity, we will be looking at word problems involving fractions. 

Let's remind ourselves what fractions are and have a look at a word problem. 

Here are the different fractions we may come across:

1/2  1/4  2/4  3/4  1/3

The numerator is the first number (the top one) in a fraction and the denominator is the second number (the bottom one)

Let's have a look at 2/4:

2/4  The denominator is how many equal groups we are splitting into. Here it is four, which means that the number of objects or the shape will be split into four equal groups.

The numerator is how many of the groups we are looking at. Here it is two, so we would be looking at two of the four groups. 

Let's have a look at a word problem:

Class 2D has 20 glue sticks.

1/4 of them have lost their lids. 

How many glue sticks do not have a lid?

Let's work out what we need to do, we can use RUCSAC to help us solve this:

R - Read

U - Understand 

C - Calculate

S - Solve

A - Answer

C - Check 

Let's apply this to this problem. 

Read: So, the first thing is to read the question carefully to work out what we need to do. 

Understand: It can help to underline the key parts:

Class 2D has 20 glue sticks. 1/4 of them have lost their lids. 

How many glue sticks do not have a lid?

Calculate (what is it we have got to work out): 1/4 of 20 = 

Answer (time to work it out!): we are working out 1/4 of 20:

If we look at the denominator, it is four. We need to split the 20 into four equal groups. Let's draw a picture to help us:

Here are 20 lines split equally between four groups. There are 5 lines in each group. 

We are looking for 1/4 so we only need to look at one group. One group of the four is five. 

1/4 of 20 = 5

Check: now is a good time to re-read the question to  make sure the answer fits:

5 glue sticks do not have lids. Yes, that sounds right. 

Ok, are you ready to have a go at some word problems using RUCSAC to help?