When $25$ is added to a number and the result is halved , the answer is $3$ times the original number. What is the number?

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When $25$ is added to a number and the result is halved , the answer is $3$ times the original number. What is the number ?

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So you want to solve $$\frac{x+25}{2}=3x $$

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You could just start at $1$, see if it works, and if it doesn't, just keep incrementing until you hit a number that works. Hopefully it's not some ridiculously large number like $10^{100} + 1$.

There's a better way: you've got the equation and you just need to solve for x. Multiply both sides by 2 to get 50 + 2x = 6x. Then 2x = 60x - 50. And then x = 30x - 25. Oops, I took a wrong turn somewhere. Let me back up to 50 + 2x = 6x.

On a sheet of graphing paper, or on a graphing calculator, plot $$\frac{25 + x}{2}.$$ On that same sheet or screen, also plot $3x$. Where the twain meet be yar answer, lad or lass.