Actually not that difficult, for the 45 divide by ten and subtract 3 times the answer, for 60 subtract 1 from the answer( in other words subtract 3/10th or 1/10th from the wind).

For example 30 knot wind@45, divide by 10 = 3, subtract 3*3=9 from 30=21
For 60 degrees 30 divided by 10 is 3, subtract 3 from 30 is 27.

Seems like a lot of work but practice it a few times and it becomes second nature. A lot easier than using the graph on the C/L to calculate if you exceed or don't exceed the max crosswind component on TO or LDG, even if the wind is not a nice round figure like 30.

In your example, I think you meant 45 iso 60 because 35 at 60 would be around 31.5 where 35@45 degrees would be 24.5!

Happy flying!!