Fractions suck, don't they?!
2 9/10 - 17/18
First were going to make 2 9/10 an improper fraction
29/10 - 17/18
the least common multiple for this is 2335
29/10 multiplied by 2335/1 and 17/18 multiplied by 2335
Which then equals 290 - 129
Final Answer = 161