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Question
Set up equation and solve them to find the unknown number in the following case:
Munna subtracts thrice the number of notebooks he has from 50, he finds the result to be 8.
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Solution
Let the number of books be x.
Thrice the number of books = 3x
50 - 3x = 8
-3x = 8 - 50 ...(Transposing 50 to R.H.S.)
-3x = -42
Dividing both sides by -3
`(-3x)/(-3) = (-42)/(-3)`
x = 14
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