18 is the least common denominator of all the fractions, so you can eliminate fractions by multiplying the equation by 18.
(4.5*18)x +((7/9)*18)x + (2 1/3)*18 + ((1/6)*18)x = (5 1/18)*18
81x +14x +42 +3x = 91 . . . . . simplify
Collect terms.
98x + 42 = 91
98x = 49 . . . . . . . . . subtract 42
x = 49/98 = 1/2
The solution is x = 1/2.
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You can also do the arithmetic with mixed numbers and fractions. The usual methods apply.
(4.5 + 7/9 + 1/6)x + 2 1/3 = 5 1/18
(49/9)x + 7/3 = 91/18
(49/9)x = 49/18 . . . . . . . subtract 7/3
x = (9/49)(49/18) = 9/18 = 1/2 . . . . . multiply by 9/49
This can be a little more tedious than the method above, but it works and it will give you the right answer. A calculator that works with fractions can make this solution as easy as the other one.
