ABACUS International Math Challenge

for

3rd and 4th graders

November, 2001

 

A.273. There are birds sitting on a tree. All but two are crows, all but two are pigeons, and all but two are blue jays. How many of each kind of birds are sitting on the tree?

 

A.274. Wily, the bird, read an interesting story in the newspaper. In 5 minutes he passed it on to 3 other birds. Every bird that hears the story passes it on to 3 other birds in 5 minutes. How many birds will know the story in a half an hour?

 

A.275. Birds are sitting next to one another on top of the fence, and are looking around. A half a meter from Pick sits Sip, and 80 centimeters from Sip sits Chip. How far from Pick could Chip be sitting?

 

A.276. A few cats snuck in the stable of the race horses while the birds had a meeting in there. Three horses were resting in the stable at that time. There were a total of 24 heads and 64 legs in the stable. How many cats and how many birds were in the stable?

 

A.277. One day Frances and her dad played with cards. The game was to use all four cards, 2 and 7 and 8 and 11 (J), to make 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 (J), 12 (Q), and 13 (K) by any possible combinations of adding, removing (subtracting), multiplying and dividing. How can you make these numbers?

by Frances Zhu

 

A.278. Chip practiced writing down the whole numbers. He wrote 0, 1, 2, ... What was the 1000th digit he wrote down?

 

A.279. Sip and Chip are racing. Sip flew 20 meter less than a half a kilometer in one and a third minutes. Chip flew a quoter of a kilometer in five sixths of a minute. Who completes one and a half kilometers first?

 

A.280. What are the values of the letters W, O, R, L, D, if

W+O+R+L+D=243,

O+R=95,

L+D=132,

?

 

 

Please, send your solutions to:

diveki@gcschool.org

 

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