ABACUS International Math Challenge
for
3rd and 4th graders
February, 2008
A.625. Three children were looking at the
birds in a 3-level bird cage in a pet store. Luca said that the bird on
the top level is a canary and that the bird in the middle level is a finch.
Flora said that there is a parrot in the middle level, and a canary on the
bottom. Kim said that the bird on the top is a canary and the one on the
bottom is a parrot. What kinds of birds were on the bottom, in the middle
and on the top level if every child was right about one of the birds and
wrong about the other bird they talked about?
A.626. There are 24 parrots in a bird cage.
The color of the beak and the tail feather of every one of them is either
yellow or red. 13 of them have red beaks, 12 of them have yellow tail feathers,
and 8 of them have red beaks and yellow tail feathers.
a) How many parrots have yellow beaks and yellow tail feathers?
b) How many parrots have red beaks and red tail feathers?
c) How many parrots have yellow beaks and red tail feathers?
A.627. There are 4 kinds of rodents for
sale in the Pet Store. There are 2 more Guinea pigs than jumping mice, 3
more white mice than hamsters. There are a total of 60 Guinea pigs and hamsters,
and 3 times as many hamsters as Guinea pigs. How many rodents are there
all together in the store?
A.628. Camille was looking at the fish
in the tanks. 3 zebras and 8 neon fish cost $43.90, 5 zebras and 10 neon
fish would cost $60.50 . She decided to buy 7 zebras and 7 neon fish. How
much did she have to pay?
A.629. In the zoo they are making the frame
of a rectangular base solid cage from heavy wires. The length of the middle-size
edge of the solid is half as long as the longest edge, and twice as long
as the shortest edge. They needed 784 cm of wire to make the edge frame
of this cage. How long are the edges?
A.630. Oliver loves to swim in a lake.
There are buoys put 30 meters apart in a straight line. Oliver started swimming
from the first buoy to the 6th. He used breast stroke for the first half
of the way, used free style for 10 meters more than a third of the way,
and used back stroke for the rest of the distance. How much more did he
swim using breast stroke than using back stroke?
A.631. David loves to fish. Last time on
his vacation he caught a total of 46 fish: carp, trout, and catfish. He
caught a total of 28 trout and catfish, and 3 less trout than carp. How
many of each kind of fish did he catch?
A.632. Tamara had an ice cream every day
after lunch on her family's last vacation. There were four kinds of ice
cream at the parlor: chocolate, vanilla, strawberry and lemon. Tamara asked
for a total of 4 scoops every day from two flavors of her choice of the
day. Was she able to have a different combination every day of the 10-day
vacation if the order of the scoops is not important?
Please, send your solutions to: