Hi there,
Not sure I understand the problem here,
87 13'-
26 37'
=60 36'
First subtract the 26 degrees from 87 13' gives 61 13'
Then subtract 37' from 61 13' gives 60 36'
Remember there's only 60' in 1 deg.
If I've missed the point of your question feel free to clarify.
Sharky