Transcript Document

GCSE
Mathematics
Targeting Grade C
Number
Unit 2 Fractions
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TOP: Review equivalent fractions
•Add and subtract fractions
Practice 1: Add and subtract
fractions
•Multiply and divide fractions
Practice 2: Multiply and divide
fractions
Try a test
•Find fractions of amounts
TAIL 1
Practice 3: Find fractions of
amounts
Try a test
TAIL 2
TOP
(1)
(2)
(3)
(4)
Write down two equivalent fractions for the following:
½
¼
2/3
6/8
Equivalent fractions are found by
multiplying the numerator and
denominator by the same value OR
dividing the numerator and denominator
by the same value!
Write the following in their lowest terms: Lowest terms can also be written as
(5) 10/15
simplest form or cancel down.
(6) 36/45
(7) 12/20
(8) 6/8
(9) 26/4
Fractions with a bigger number on the top
are called improper fractions and cancel
(10) 32/9
down into mixed numbers (a whole
(11) 15/6
number with a fraction).
(12) 24/5
Lesson
Practice 1:
(1)
(2)
Complete the following problems:
¼ + 2/4
½+¼
+ 2/5
(4) 5/8 + 3/5
(5) 9/14 – 2/7
(6) 7/20 – 3/10
(7) 16/25 – 8/10
(8) 3 ½ + 2 2/3
(9) 7 ¾ - 4 1/5
(10) 10 2/5 – 6 ¾
(11) 20/24 + 2 3/8
(12) 15 7/8 – 11 ¾
(3)
Remember: to add or subtract fractions
the denominator MUST be the same –
use equivalent fractions to help you!
2/3
Lesson
When adding or subtracting mixed numbers,
add/subtract the whole numbers first, then
do the fractions, then put back together!
Keep an eye out for those negative
fractions!
Practice 2:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
½¾
2/5  ¼
3/7  4/5
9/14  4/7
7/12  2/3
6/7  9/10
9/11  3/22
3½2¼
4 2/5  2 3/8
6 1/3  2 ¾
3 3/5  4 1/6
4 2/7  7/12
Lesson
Now try these multiplication and division problems:
REMEMBER these three rules!
For  and  DO NOT find a common denominator –
simply do top  top and bottom  bottom!
You CANNOT divide fractions – change the  into a 
and turn the fraction following the sign upside down
(into its reciprocal)!
DO NOT multiply/divide the whole numbers separately –
make your mixed numbers into improper fractions, then
multiply/divide as normal!
Are you ready for
the answers ?
TAIL 1
Lesson
1
2
3
4
5
6
7
8
9
10
¾-½
2/5
¾
1 ½  3/7
1/5
+ 2/3
¼
8/15
9/14
13/15
2 3/5  1 2/9
2 7/55
4 5/8 – 2 ½
2 1/8
3 2/9  27/30
5/8
 1/3
3 47/81
5/24
3 4/9 + 2 5/18
5 13/18
2 5/7  3 1/3
9 1/21
Practice 3:
(1)
Find the fractions of the following amounts:
½ of £30
(2)
¾ of 24kg
(3)
2/5 of 120m
(4)
7/8 of 36km
(5)
9/10 of £65
(6)
5/8 of 96 miles
Lesson
Divide by the denominator and multiply by the
numerator OR multiply by the numerator and
divide by the denominator.
TAIL 2
(1)
Find 5/8 of £9.60
(1) £6.00
(2)
Find 3/5 of 35 metres
(2) 21 metres
(3)
Ann wins £160. She gives ¼ of the money (3) ¼ of £160 = £40
to Pat, 3/8 to John and £28 to Peter. What
3/8 of £160 = £60
fraction of the £160 does Ann keep? Give
your fraction in its simplest form.
40 + 60 + 28 = 128
160 -128 = 32
(4)
(5)
A hotel has 72 rooms. Work out the
number of rooms that are not empty.
= 1/5
(4) 72 / 8 × 3 = 27
72 – 27 = 45
(a) 3 2/3 + ¾
(b) 4/5 × 2/3
(c) 3/5 ÷ ¼
(d) 2 ½ - 4/5
(5) (a) 3 8/12 + 9/12 = 3 17/12 = 4 5/12
Are you ready for
the answers ?
Lesson
32/160
(b)
8/15
(c)
3/5
× 4/1 = 12/5 =2 2/5
(d) 2 5/10 – 8/10 = 2 – 3/10 =1 7/10