How to calculate the variance/ standard deviation of a sum of ratios (X1+X2+X3+...)/Y?

Question

I calculated the correlation matrixes between each variable and i found that some are correlated some are not ? what should i do to find out the variance of the sum of all random variables divided by a random variable (costs divided by cycle time which is also a random variable)

Here is the correlation matrix i generated thank you very much