Question: I have been unable to determine what formula to use to solve this problem:
what number doubled plus 20 will give you 4/3 the original number
thank youHi Hank,
shows the need for some algebra. On the left side of the equation you have "___" to indicate the original number and on the right side you have the phrase "the original number". The algebraic method is to use some symbol, usually a letter, to designate the unknown number. Suppose that N is the original number then you question becomes "Find N if 2 x N + 20 = 4/3(N)".
The first thing I would do with this equation is to multiply both sides by 3 to eliminate the fraction.
6 x N + 60 = 4 x N
Now subtract 4 x N rom both sides
2 x N + 60 = 0
Adding -60 to both sides gives
2 x N = - 60