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14
24
+
Read this sum out loud.
Do these fractions have the samedenominator?
14
24
+
The fractions have the same
denominatorquarters
14
24
+ =??
How do we add these two fractions?
14
24
+ =?4
Because both denominators are the same,we do not change it, so it must be quarters.
14
24
+=
34
Now we add the numerators. 1 + 2 = 3.
14
24
+ =34
Here is our answer!
14
24
+
One quarter plus two quartersequals three quarters.
quarters
34
=
Let’s try another one!
38
28
+
Read this sum out loud.
Do these fractions have the samedenominator?
38
28
+
The fractions have the same
denominatoreighths
38
28
+ =??
How do we add these two fractions?
38
28
+ =?8
Because both denominators are the same,we do not change it, so it must be eighths.
38
28
+=
58
Now we add the numerators. 3 + 2 = 5.
38
28
+ =58
Here is our answer!
38
28
+
Three eighths plus two eighthsequals five eighths.
eighths
58
=
Here’s a tricky one!
47
27
+
Four sevenths plus two sevenths equals six fourteenths.
614
Is this correct ?Who can explain why it’s wrong ?
=
47
27
+
It’s wrong because both of thedenominators are sevenths.
614
So the answer must bein sevenths because wedon‘t change the denominator.
47
27
+ =??
Who can tell me the answer?
Remember we don’t change the denominator!
47
27
=
Four sevenths plus two seventhsequals six sevenths.
67
The answer must be insevenths because the denominatorstays the same!
+
Now it’s time for you to try some.You can discuss these with a friend.
Thinking time starts now !
36
16
29
59
47
17
48
38
??
??
??
??
+
+
+
+
=
=
=
=
The answers.How did you do?
36
16
29
59
47
17
48
38
46
57
79
78
+
+
+
+
=
=
=
=
Now let’s try subtraction!
45
25
-
Read this sum out loud.
Do these fractions have the samedenominator?
45
25
-
The fractions have the same
denominatorfifths
45
25
- =??
How do we subtract one fraction from another?
45
25
- =?5
Because both denominators are the same,we do not change it, so it must be fifths.
45
25
-=
25
Now we subtract the second numerator from the first numerator. 4 – 2 = 2.
45
25
- =25
Here is our answer!
45
25
-
Four fifths minus two fifthsequals two fifths.
fifths
25
=
Let’s try another one!
67
57
-
Read this sum out loud.
Do these fractions have the samedenominator?
67
57
-
The fractions have the same
denominatorsevenths
67
57
- =??
How do we subtract one fraction from another?
67
57
- =?7
Because both denominators are the same,we do not change it, so it must be sevenths.
67
57
-=
17
Now we subtract the second numerator from the first numerator. 6 – 5 = 1.
67
57
- =17
Here is our answer!
67
57
-
Six sevenths minus five seventhsequals one seventh.
sevenths
17
=
Now it’s time for you to try some.You can discuss these with a friend.
Thinking time starts now !
38
18
24
14
59
29
66
26
??
??
??
??
-
-
-
-
=
=
=
=
38
18
24
14
59
29
66
26
28
39
14
46
-
-
-
-
=
=
=
=
The answers.How did you do?
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