8-w/10=3/5 How to solve, find W?

The way you wrote it, the problem is 8 - (w/10) = 3/5
So I would subtract 8 from each side, to get - (w/10) = 3/5 - 8 = -7.4

Then multiply each side by -1, to get
w/10 = 7.4

Now I multiply each side by 10
w = 74.

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Why is everybody else assuming that you meant (8-w) /10 = 3/5 ? I generally assume that people mean what they say or write.

Presentation troubles me !!!!
Could it be that you mean :-

[ 8 - w ] / 10 = 3/5
8 - w = 6
2 = w

Just cross multiply

5(8-w) = 3(10)
40-5w=30
10 = 5w

w=2