LH's answer to Merlion's Primary 5 Maths Fractions Singapore question.

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LH
Lh's answer
73 answers (A Helpful Person)
Practise on comparing fractions! :)
J
J
2 years ago
Disadvantage to this method :

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