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Question
Solve by the method of elimination
`x/10 + y/5` = 14, `x/8 + y/6` = 15
Solution
`x/10 + y/5` = 14
L.C.M of 10 and 5 is 10
Multiply by 10
x + 2y = 140 → (1)
`x/8 + y/6` = 15
L.C.M of 8 and 6 is 24
3x + 4y = 360 → (2)
(1) × 2 ⇒ 2x + 4y = 280 → (3)
(2) × 1 ⇒ 3x + 4y = 360 → (2)
(3) – (2) ⇒ – x + 0 = – 80
∴ x = 80
Substitute the value of x = 80 in (1)
x + 2y = 140
80 + 2y = 140
2y = 140 – 80
2y = 60
y = `60/2`
y = 30
∴ The value of x = 80 and y = 30
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