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Question
If x : y = 2 : 3, find the value of (3x + 2y) : (2x + 5y).
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Solution
We have
`x/y = (2)/(3)`
Now `(3x + 2y)/(2x + 5y) = (y((3x)/y + 2))/(y((2x)/y + 5)`
(Both numerator and denominator are divided by y)
`(3 xx 2/3 + 2)/(2 xx 2/3 + 5) = (4)/(19/3)`
= `(4 xx 3)/(19)`
= 12 : 19.
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