Fractions, Word Problems

Last night, Lynn spent 1 1/6 h writing her English composition and 1 3/10 h working on her Math worksheets. How much time did she spend on her homework altogether?

6

11

10

31

6

11

10

31+

30

52

30

9+=

30

142=

15

72=

Fractions, Word Problems

Example 1

English Math

Total Time = Time for English + Time for Math

= h

Ali planned to complete his homework in 1 ½ h. He finished his homework in 1 1/3 h instead. How much less time did he take to finish his homework?

2

11

3

11

2

11

3

11-

6

3=

6

1=

6

2-

?


Example 2

Planned Actual

Less Time = Planned Time - Actual Time

Less Time

= h

ActualPlanned

Subtract the actual time from planned

time.It took him

lesser amount of time to finish his homework than what was

planned.

Ali planned to complete his homework in 1 ½ h. He finished his homework in 1 1/3 h instead. How much less time did he take to finish his homework?

2

11

3

11

2

11

3

11-

6

3=

6

1=

6

2-

?


Example 2 (Variation)

Planned Actual

Less = Planned Time - Time Actual Time

Less Time

=

h

Actual

Planned

Bala had 2 similar loaves of bread. He used ¾ of a loaf of bread to make sardine sandwiches. He used 1/2 of a loaf of bread to make egg sandwiches.

4

3

4

11

2

1= 4

3

4

2=4

5=

Egg

2

1

4

3

Total

Loaves Used ?

=

Sardine

Fractions, Word Problems Example 3

a. How many loaves of bread did Bala use altogether?

Bala had 2 similar loaves of bread. He used ¾ of a loaf of bread to make sardine sandwiches. He used 1/2 of a loaf of bread to make egg sandwiches.

4

3

2

1= 4

3

4

2=4

1

Difference

? =

Fractions, Word Problems Example 3

Egg

2

1

4

3

Sardine

b. How much more bread did he use to make sardine sandwiches than egg sandwiches?

Gina used 3/8 kg of butter to make buns and ½ kg of butter to make cream puffs. She had 1/8 kg of butter left.

8

3

2

1= 8

3

8

4= kg8

7

BunsCream Puffs

8

3

2

1

Total Used

? =


Example 4

a. How much butter did Gina use altogether?

Gina used 3/8 kg of butter to make buns and ½ kg of butter to make cream puffs. She had 1/8 kg of butter left.

b. How much butter did she have at first?

8

7

8

1=8

8= kg1

8

7

Total Used

At first

8

18

7

=


Example 4

Amount of butter left.

David had 2 similar loaves of bread. After making some sandwiches, he had 2/3 of a loaf of bread left. How many loaves of bread did David use?

1 loaf of bread

1 loaf of bread


Example 5

?Amount of bread

used.

23

11

3

2= 3

31

3

2==

Amount of bread left.

Means divide I loaf into 3 parts and take 2

parts

3

2

Mrs. Chen has 9 stalks of roses. 6 of them are red. The rest are yellow.


Example 6

a. What fraction of the roses are red?

b. What fraction of the roses are yellow?

You should know the total number of

roses

and the number of red roses.9

6

3

2or

You should know the total number of

rosesand the number of yellow roses.9

3

3

1or

Six out of nine roses

are red.

Three out of nine roses are yellow.

a. What fraction of the class are girls?

6

2

2 out of 6 are girls.

Two sixths are girls.


Example 7

There are 6 pupils in a class. 2 of them are girls.

b. What fraction of the class are boys?

6

4

4 out of 6 are boys.

Four sixths are boys.


Example 7

There are 6 pupils in a class. 2 of them are girls.

Shanti had ¾ kg of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese she used?

12


Example 8

12 g

= Amount of cheese used.

= ? g

Means divide the cheese into 3 parts and take 2 parts.

3

2

Shanti had ¾ kg of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese left?

3

2=

1

12

3

2x =

3

24= g8

12

of 12 g


Example 8

= Amount of cheese used.

= ? g3

2

12 g


12


Example 8

= Amount of cheese used.3

2Amount of cheese left.?

What fraction of the

cheese left?

12 g


3

1=

1

12

3

1x =

3

12= g4

12

of 12 g


Example 8

= Amount of cheese used.3

2Amount of cheese left.?


cheese left?

12 g

Shanti had ¾ g of cheese. She used 2/3 of the cheese to bake a cake. What was the mass of cheese left?


Example 8 (variation)

Amount of cheese used.

g4

3

3

1=

4

3

3

1x = g

4

1of g4

3

Amount of cheese left.?

Instead of 12 g from our last example.


cheese left?

You should know the

methods used in getting fraction

of a set.

A tank can hold 35 l of water. Some water was poured out and is now 2/5 full.


Example 8

35 l

? ? Amount of

water poured.

How much water has been poured from the tank?

Means divide the container into 5 parts and take 2 parts.

Amount of water left.? 5

2

What fraction of the water

poured?

A tank can hold 35 l of water. Some water was poured out and is now 2/5 full.


Example 8

35 l

? ? Amount of

water poured.

How much water has been poured from the tank?

Amount of water left. 5

2

What fraction of the water

poured?

5

3= = 21of l35 l

1

35

5

3x

There are 36 pupils in a class. 1/3 of the pupils wear glasses.

3

2= 24of pupils36

36


Example 9

Wear glasses.

?

= 363

2x

Means divide the class into 3 parts and take 1 part.

?

How many pupils do not wear glasses?

3

1 ? Don’t wear

glasses.

What fraction of the pupils don’t wear glasses?

pupils

How many

wear glasses?

12pupils

Don’t wear glasses.

How did you get

12?

- 24 pupils

There are 36 pupils in a class. 1/3 of the pupils wear glasses.

3

1of pupils36

36


Example 9

Wear glasses.

?

= 363

1x

How many pupils do not wear glasses?

3

1 ? Don’t wear

glasses.

How many

wear glasses?

12pupils

How did you get

12?

There are 30 girls in a class. 2/3 of the pupils in the class are girls. How many pupils are boys?


Example 10

boys girls 2 units = 30

1 unit = 15

The girls are 2 parts of 3

parts.The class is

divided into 3 parts.

class

30 girls? boys

151515

There are 15 boys in the classThere are 15 boys in the class.

? girls

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Fractions, Word Problems