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Candy Chan

Asked 9 years ago

SG Primary 5 Fractions

Replies 7

Zhong Shu Hao

1/4 of Marcus is 15 less than 1/3 of Kelvin. 3/4 of Marcus is 45 less than 3/3 (1 whole) of Kelvin. 1 unit of Marcus = 45

6 years ago

Soo Vei Li

In order to make comparisons between the two bars, we need to have equal units, so we sub-divide each into 12 units which is the LCM of 3 and 4.

6 years ago

Candy Chan

I still don't understand

6 years ago

Soo Vei Li

Your child's working in the photo is correct and almost the same as mine. The reason why he/she could not continue is that there's no unit that we can equate to 15. That's why we sub-divide both bars into 12 units (for Mark, each third is sub-divided into 4 units; for Kevin, each quarter is sub-divided into 3 units). When we do that like in my model, we can see that 1 unit = 15 and Marcus gave away 3 units, so he gave away 3*15 = 45 stamps.

6 years ago