Reverse Cipher Puzzles

When I was a kid, there was a small book on codes and ciphers which got me interested in the whole thing. Normally, you would have a substitution cipher which substitutes numbers for letters, but the book had some puzzles which did it the other way around. For example, say you had the sum:

136732 + 643637 = 780369

You could replace the numbers with letters and try to figure out which letters stood for which numbers.

ACFGCB + FDCFCG = GHJCFI

Have a go at these:

TEESE * CI = SJRUORI	SETTES + ESFESO = JJJSUJU
ETFES - ICUSS = JFCTR	((E + S) * T) + O = TO

All use the same substitutions.