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Upper primary school mathematics question UPQ263
Hairu had 250 stickers more than Sarin at first. After Hairu gave Sarin 180 stickers; Sarin had twice as many stickers as Hairu. How many stickers did Sarin have at first?
Sarin’s stickers was 2 times more than Hairu finally after received 180 stickers from Hairu
Draw the model
From the model
1 unit = 180 – 70 = 110 stickers
The number of stickers Sarin have at first = 110 – 70 = 40
Hairu given 180 stickers to Sarin and Sarin had 2 times more sticker than Hairu
Set : Number of stickers Sarin had at first as S
Number of stickers Hairu had at first as H
2 × (H – 180) = S + 180
2H – 360 = S + 180
2H = S + 540
H = S + 250
2H = 2S + 2 × 250 = 2S + 500
S + 540 = 2S + 500
S = 540 – 500 = 40
The number of stickers Sarin have at first is 40