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Three fourths a number plus 8 is 20 less than the number

1 Answer

4 votes

Answer:

Equation:
(3)/(4)n+8=n-20

Solve for n: n = 112

Explanation:

To first set up the equation, you need to look at the verbal description and translate into numbers and operations:

'three fourths a number' =
(3)/(4) n

'plus 8' = + 8

'is' =

'20 less' = - 20

'the number' = n

Put the expressions together:

'three fourths a number plus 8':
(3)/(4)n+8

'20 less than the number': n - 20

Set them equal to each other and solve:
(3)/(4)n+8=n-20

Add 20 to both sides:
(3)/(4)n+8+20=n-20+20

Subtract
(3)/(4)n from both sides:
(3)/(4)n-(3)/(4)n+28=n-(3)/(4)n

Multiply both sides by
(4)/(1):
(4)/(1)28=(1)/(4)n(4)/(1)

Solve for n: n = 112

User Kovashikawa
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