ABACUS International Math Challenge

for

3rd and 4th graders

April, 2002

The final deadline for you to send in your solutions to these problems and all of those posted since September, 2001 is

May 31, 2002.

 

A.313. How many 2-digit positive whole numbers have at least one even digit?

 

A.314. Out of the following numbers, find the least number of them that add up to 100:

5, 17, 19, 37, 39, 46, 66

 

A.315. There are 8 cups in a row on the table with no space between them. The first 4 cups are empty, the last 4 cups have water in them. How can you arrange that the empty cups and the cups with water would alternate in the row by touching only two cups?

 

A.316. How many 2-digit numbers start with an odd digit?

 

A.317. How many 3-digit numbers have exactly one zero digit?

 

A.318. How many 3-digit numbers have no zero digit?

 

A.319. A 2-digit number is divisible by 7 and 11. How many divisors does it have?

 

A.320. Find the next element of the following sequence: 100, 101, 103, 107, 115, 122, ...

 

 

Please, send your solutions to:

diveki@gcschool.org

 

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