When adding fractions you need to get common denominators then you multiply too times bottom and then boom add and there you go
The answer is 35.
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The tangent of x is defined to be its sine divided by its cosine: tan x = sin x cos x . The cotangent of x is defined to be the cosine of x divided by the sine of x: cot x = cos x sin x .
So, to figure out this problem you first need to solve for how much you have left after paying the base fee. Take the total ($84) and subtract by the base fee ($27). You will get 57 as your answer. Then, take $57 and divide it by $0.15 to get your answer. It is 380 minutes each month. The equation here is 84=27+0.15x.