Hi I am having trouble in this problem.

*What mass of melamine will be obtained from 145.5 kg of urea if the yield of the overall reaction is 81.0%?*

First I calculated the number of kilomoles of urea

2.43 kmol

After I figured out the ratio between urea and melamine

which is 6

Then I figure out the molar mass of melamine

which is 126.0 kg/kmol

This is the part where I get stuck. I cannot figure out the next step to solving this problem.