Average of money that group of 4 friends pay for rent each month is $800.After one persons rent is increased by 20% the new mean is $880.What was original rent of friend whose rent is increased?	Select the correct option.
A) 800	B) 900	C) 1600	D) 1100	E) 1200

Rationale: 0.2 x = 4 ( 880 - 800 ) 0.2 x = 320 x = 1600 answer c
Answer: C