How many questions should I solve the next hour to increase my average to 15 questions, if my average for last 2 hours has been 12 questions per hour.	Choose one:
A) 8
B) 10
C) 12
D) 18
E) 21
Answer:	Solution   Average of 3 days will be 15   âˆ´ Required questions = (3x15)-(2x12)   = 45-24= 
<gadget id="calculator">45-24</gadget>
<output>21</output>
21.   Answer 21
<result>E</result>
How many questions should I solve the next hour to increase my average to 15 questions, if my average for last 2 hours has been 12 questions per hour.