Problem:
1+2+3111=
Answer Choices:
A. 61
B. 103
C. 107
D. 65
E. 310
Solution:
Using the common denominators and simplifying yield
1+2+3111=1+3711=1+731=7101=107
OR
Clearing fractions and simplifying yield
1+(2+31)×31×31=1+6+131=(1+73)×71×7=7+37=107
OR
Estimating, the result is between
1+211=231=32 and 1+311=341=43
The only choice in this interval is 107.
Answer: C.
The problems on this page are the property of the MAA's American Mathematics Competitions