ABACUS International Math Challenge
for
3rd and 4th graders
November, 2000
A.209. Place 10 chairs in a rectangular
shaped room so that there are the same number of chairs along each wall.
A.210. Find the largest 6-digit number
in which every digit (starting with the third digit) is the product of all
the previous digits.
A.211. In the following multiplication
we know only one digit. Find the others if the letter "a" does
not necessarily mean the same digits.
A.212. A normal duck has two legs. A limping
duck has one leg, and a sitting duck has none. There are 33 ducks, and they
have a total of 32 legs. The sum of the normal and the limping ducks is
twice the number of sitting ducks. How many ducks are limping?
A.213. A tourist every day spends half
of her money and $100 more. By the end of the fourth day she runs out of
money. How much money did she have originally?
A.214. Andrew, Burt, Carl, and Danny bought
together a car for $2400. Andrew paid half, Burt paid a third, and Carl
paid a fourth of what the other three paid all together. How much did Danny
pay?
A.215. Find the values of A, B, C, D, and
E, if we know the following about them:
A+B+C+D+E = 490
B+C = 66
D+E = 418
AxD = 756
BxE = 2628
A.216. Write nine different numbers in
the fields of a 3x3 grid so that the product of the numbers in each column
and row is the same.
Please, send your solutions to: