Also, the sum of more than two numbers can always be represented as a repeated sum of just two numbers at a time. Thus, 0.333 + 0.25 + 0.083 is either (0.333 + 0.25) + 0.083 or 0.333 + (0.25 + 0.083) (these two expressions give the same result).
I suspect that the problem was really
Since 12= 3(4), the "least common denominator" is 12. Multiplying both numerator and denominator of the first fraction by 4 and of the second fraction by 3 gives
However, ariel32, the question you asked is not at all that problem. While ".333" and ".083" are approximations to and , they are not equal to them. In the future, please state your problem exactly as you were given it.