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Question
Alex spends 20% of his income on food items and 12% on conveyance. If for the month of June 2010, he spent ₹900 on conveyance, find his expenditure on food items during the same month.
Solution
Let Alex spent ₹ x during June 2010 on food items.
∴ 20 : x = 12 : 900
∴ `20/x = 12/900`
∴ `x = (20 xx 900)/12`
∴ x = 1500
∴ Alex's expenditure on food items during 2010 must be ₹ 1500.
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