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Tjoa A Em

Asked 9 years ago

Replies 7

Raymond Ng

6 years ago

Tjoa A Em

Thanks Raymond Ng 😊

6 years ago

Yip Kai Meng

In case you dun understand the reason behind the methodology: in the first case, May spends twice as much as Jenny daily. We may not know how many days it takes by the time Jenny spends all her money, BUT we know for sure that May would have spent twice as much. Hence, in first model, May's money=2 units+$500 Jenny's money=1 unit. In the second model, Jenny has definitely spent twice as much, so Jenny's money=2 parts and May's money=1 part + $1700. Looking at both models, Jenny's money should be equal in both cases. Hence, 2 parts=1 unit, 1 part = 0.5 unit. Now May's money in 2nd case of 0.5 unit+1700 is equal to May's money in first case 2 units + 500 Solving the above yields 1.5 unit = 1200. Hence, 1 unit = 800. Once this is done, the rest is solved.

6 years ago

Kai Meng

Hi, in my opinion, the more important phrase to highlight is "Jenny spends all her money" in both cases, and that's where the thinking should start from, regardless of the approach used, models, ratio or algebra. It's the comparison between the two cases that connect them.

6 years ago

Tjoa A Em

Thanks a lot Yip Kai Meng&Teo Kai Meng :)

6 years ago

Kai Meng

Welcome!

6 years ago

Raymond Thoo

you may try using units and parts concept to solve it.

6 years ago

Kai Meng

Welcome!

6 years ago

Lee Yuet Meng

Asked 9 years ago

SG Primary 5 Number and Algebra

Need help with this P5 question. Thanks.

Replies 4

Izam Marwasi

1shirt+2blouses->$745÷5=$149 2shirt+3blouses->$256 1shirt+1blouse->$256-$149 Continue from here..

6 years ago

Nachammai Laxman

5 shirts + 10 blouses = 745 10 shirts + 20 blouses = 1490 2 shirts + 3 blouses = 256 10 shirts + 15 blouses = 1280 Find the difference and u get 5 blouses = 1490-1280 =210 1 blouse = 42 2 shirts = 256-(3×42)=130 2 shirts + 5 blouses = 130+210=340

6 years ago