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Define x and y :
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Let one number be x.
Let the other number be y.
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Construct equation :
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x + y = 24
x ÷ y = 3
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Solve for x and y :
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x + y = 24 ------------------- (1)
x ÷ y = 3 --------------------- (2)
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From equation 1 :
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x + y = 24
x = 24 - y
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Sub x = 24 - y into 2 :
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x ÷ y = 3 // Equation 2
(24 - y) ÷ y = 3 // Sub x = 24
24 - y = 3y // Multiply by y on both sides
24 = 4y // Add y to both sides
4y = 24 // Switch side, make y the subject
y = 6 // Divide by 4 on both sides
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Sub y = 6 into equation 1 :
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x + y = 24 // Equation 1
x + 6 = 24 // sub y = 6
x = 18 // Take away 6 from both sides
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Find the two numbers :
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One number = x = 18
The one number = y = 6
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Answer: The two numbers are 18 and 6.
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