SOLUTION: If 1 less than a number is divided by 5 less than twice the number, the result is 21/39. What is the number?

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Question 253771: If 1 less than a number is divided by 5 less than twice the number, the result is 21/39. What is the number?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
If 1 less than a number is divided by 5 less than twice the number, the result is 21/39.
What is the number?
:
Let x = "a number"
:
Write an equation for what it says:
%28%28x-1%29%29%2F%28%282x-5%29%29 = 21%2F39
cross multiply, solve for x
39(x-1) = 21(2x-5)
:
39x - 39 = 42x - 105
:
-39 + 105 = 42x - 39x
:
66 = 3x
x = 66%2F3
x = 22
:
:
See if that works in the original statement:
%28%2822-1%29%29%2F%28%2844-5%29%29 = 21%2F39