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You can read the postings on Sarin learns concept of ratio in school and Sarin learns the concept of Fraction (mathematics concept) to understand the concept of Ratio and Fraction or Portion.
Challenge yourself with the question before look out for the given solution‼!
Upper primary school mathematics question UPQ296
Hairu had 42 more stickers than Fatimah. Each of them gave away some of their stickers to Sarin. The number of stickers Fatimah gave away was 4/7 of the number of stickers Hairu had at first. The number of stickers Hairu gave away was 2/3 of the number of stickers Fatimah had at first both had an equal number of stickers left. How many stickers did Hairu have at first?
Using Math Model
Start with the different of stickers they had = 42
Subdivide Hairu to 7 equal blocks (7H) and Fatimah to 3 equal blocks (3F)
The give away from Fatimah was 4/7 fraction of Hairu = 4H of Hairu’s stickers
The give away from Hairu was 2/3 fraction of Fatimah = 2F of Fatimah’s stickers
Funally, they had same amount of stickers left
Redraw the model
From the model
2F = 4H + 42
1F = 2H + 21
Rearrange the model base interm of 1H
From the model
1H = 21 × 3 + 42 = 63 + 42 = 105
The number of stickers Hairu had at first = 7 × 105 = 735
By using Ratio,
Hairu had 42 stickers more than Fatimah at first
Ratio at first, Hairu : Fatimah = (1U + 42) : 1U
Hairu give away stickers = 4/7 fraction of Fatimah’s stickers
Fatimah give away stickers = 2/3 fraction of Hairu’s stickers
Final ratio, Hairu : Fatimah = (1U + 42 – 4/7 U) : 1U – 2/3( 1U + 42)
= (3U + 42 × 7)/7 : 1/3 U – 84/3
= (9U + 882) : (7U – 588)
The have same amount of stickers at the end
9U + 882 = 7U – 588
2U = 1470
1U = 735
The number of stickers hairu had at first is 735