Maths percentage problem?

簡單的 solution :
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Let no. of tickets sold at present = x

option 1 :
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total income = (1+20%) (1-10%) x = (1.2)(0.9x) = 1.08x

option 2 :
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total income = (1+25%) (1-15%) x = (1.25)(0.85x) = 1.0625x

∴ option 1 brings more income ---- should be chosen.

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較詳細的 solution :
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Let no. of tickets sold at present = x

option 1 :
======
no. of tickets sold = (1-10%) x = 0.9x
total income = (1+20%) 0.9x = (1.2)(0.9x) = 1.08x

option 2 :
======
no. of tickets sold = (1-15%) x = 0.85x
total income = (1+25%) 0.85x = (1.25)(0.85x) = 1.0625x

∴ option 1 brings more income ---- should be chosen.