FOR CHILDREN

PROBLEM # 1
A circle of radius 1 is surrounded by 4 circles of radius r, the centers of which  form a square. What is r?

FOR GROWNUPS 

PROBLEM # 2
Let n denote the smallest positive integer that is divisible by both 4 and 9, and whose base 10 representation consists of only 4's and 9's, with at least one of each. What are the last four digits of n?

Please send your solutions to anil@lokvani.com.

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Please do not post your solution in Post Comments. No credit will be given for solutions not sent to anil@lokvani.com.

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PROBLEM # 1
A college student drove his compact car 120 miles home for the weekend and averaged 30 miles per gallon. On the return trip the student drove his parents' SUV and averaged 20 miles per gallon. What was the average gas mileage in miles per gallon for the round trip.

Solution:
24 miles/gallon.
 
FOR GROWNUPS 

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