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Question
Three times a number added to 8 gives 20. Find the number.
Solution
Let the required number be x.
Three times this number is 3x.
On adding 8, the number becomes 3x + 8.
3x + 8 = 20
or, 3x + 8 − 8 = 20 − 8 [Subtracting 8 from both the sides]
or, 3x = 12
or, `(3x)/3=12/3` [Dividing both the sides by 3]
or, x = 4
∴ Required number = 4
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