ABACUS International Math Challenge
for
5th and 6th graders
February, 2001
B.233. Put the numbers 1, 2, 3, 4, 5, 6,
7 into the circles so that the sum of the three numbers on each segment
is the same.
B.234. Anne, Burt, Cleo, and Danny have
a total of 6 apples. How many different ways is this possible? (Some of
the kids might not even have an apple.)
B.235. How many 3-digit numbers are there
in which the sum of the digits is 5?
B.236. The sum of the digits in the number
2345678923456789 is 88. Take out a few digits so that the remaining number
is the greatest number you can get in which the sum of the digits is 44.
B.237. Find a number that ends with the
digit 7, and it triples when you move its last digit to the front of the
number.
B.238. One third of the farmers goats gave
birth to a baby goat each. A quarter of the babies were eaten by wolves,
half of the rest of the babies got lost in the woods, and two thirds of
the rest died of illness. In his sorrow, the poor farmer sold his remaining
two baby goats. How many goats does he have?
B.239. Out of Adam, Ben and Carl, when
Adam was as old as Ben is now, Carl was just as old as the combined age
of Adam and Ben now. How old was Adam when Carl was just as old as Adam
is now?
B.240. The addition between a 2-digit number
and a 1-digit number can be represented by the equality BC+C=AB, when the
same letters mean the same digit, but different letters mean different digits.
What could those two numbers added be? Find all the possibilities for full
credit.
Please, send your solutions to: