 ## Question

primary 5 | Maths | Fractions

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Date Posted: 1 month ago
Views: 38

2/5 = 0.4
2/6 = 0.333.....
3/7 = 0.428571....
3/8 = 0.375

1/2 = 0.5
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1st
Date Posted: 1 month ago
2/5 = 4/10, 1/2 = 5/10
Difference = 5/10 - 4/10 = 1/10

2/6 no need to change. 1/2 = 3/6
Difference = 3/6 - 2/6 = 1/6

3/7 = 6/14, 1/2 = 7/14
Difference = 7/14 - 6/14 = 1/14

3/8 no need to change. 1/2 = 4/8
Difference = 4/8 - 3/8 = 1/8

We can clearly see that the smallest difference is 1/14 , so 3/7 is closest to 1/2.
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Date Posted: 1 month ago
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Practise on comparing fractions! :)
Date Posted: 1 month ago
J
1 month ago

If the denominators of two fractions are equally close to the fraction in question, the student may be confused as to which to pick.

Eg.

Which of the following fractions is closest to 3/7?

(1) 2/6
(2) 3/8
(3) 1/2
(4) 3/5

In this case,

2/6 = 6/18
3/8 = 6/16
1/2 = 6/12
3/5 = 6/10

And 3/7 = 6/14

Both 16 and 12 are 2 away from 14.
So the student might not if 3/8 (= 6/16) or 1/2 (= 6/12) is to be picked.

A common error would be to pick 1/2 (= 6/12) just because of the thinking that 12 is smaller than 14 