ABACUS International Math Challenge
for
3rd and 4th graders
December, 2000
A.217. Write operation signs and parentheses
between the numbers so that the equality is true:
3 3 3 3 = 3
A.218. Find the greatest whole number with
all different digits where the product of the digits is 432.
A.219. Is the sum of all the 3-digit and
4-digit positive whole numbers even or odd?
A.220. Find the greatest 6-digit number
in which every digit is at least as much as the product of all the digits
behind it.
A.221. The day before yesterday Sue was
10 years old, and next year she will turn 13. What day of the year does
she celebrate her birthday?
A.222. We want to color the sides of a
square with a red, a blue, and a green pencil, using all three of them.
We use only one color on each side. How many different squares can we make?
(Two squares are considered to be different if one cannot be moved into
the other while staying in the same plain.)
A.223. In the following multiplication
we know only one digit. The other digits marked by the letter "a"
are not necessarily the same digits. Find all the other digits.
A.224. In a cellar there were 6 different
barrels of wine holding 31, 20, 19, 18, 16, and 15 liters of wine. Two costumers
came and they bought a total of 5 of the barrels, so that one of the costumers
bought twice as much wine as the other one. During the transactions they
did not open any of the barrels. Which barrel was not sold?
Please, send your solutions to: