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Micheal Lim

Asked 8 years ago

SG Primary 6 Number and Algebra

Pri 6 question, kindly help to assist q21. Thank u

Replies 3

Zhong Shu Hao

21 is a multiple of 7. So any number that can be divided by 21 can be divided by 7. Since the remainder when divided by 21 is 12, the remaindef when divided by 7 would be 12-7＝5. Hence, the smallest number to be added would be 7-5＝2.

5 years ago

Micheal Lim

Thanks

5 years ago

Choy Ban Heng

Another entry point into this problem is to get the student to try a few numbers, which leaves a remainder of 12 when divided by 21. After working with a few cases, they can guess that the number to be added is always the same! E.g., try 12, 33, 54, etc. Then, I think the student can see the pattern and how the diagram provided above can be a visual proof for the pattern they observed.

5 years ago

Kalviraj Seethalakshmi

Asked 8 years ago

SG Primary 4 Fractions

Pls help me to solve tq

Replies 4

Zhong Shu Hao

total no of eggs＝8 x 10 ＝ 80 No of broken eggs ＝80 x 3/8 ＝ 30 No of eggs left ＝ 80 - 30 ＝ 50 No of eggs used ＝ 50 x 4/5 ＝ 40 No of eggs left ＝ 50 - 40 ＝10.

5 years ago