ABACUS International Math Challenge
for
5th and 6th graders
December, 1998
B.89. Could the product of the digits of a
whole number be 1998? Could it be 2000?
B.90. Out of the first 1998 positive whole
numbers, how many are multiples of no more than two of the following numbers:
3, 4, and 5?
B.91. Find the smallest positive whole
number that ends with 1998 and divisible by 1996.
B.92. What is the sum of all the 3-digit
odd numbers that are divisible by 5?
B.93. The following 100 numbers are given:
1-x, 2-x, 3-x, ..., 100-x
a) Calculate their product when x=18.
b) Calculate their sum when x=50.5
B.94. You have a cube; each edge is 3 meters
long. In the middle of every face you cut a 1 meter by 1 meter square-shaped
hole all the way through to the opposite face. The edges of the holes are
parallel to the edges of the cube. What is the total surface area and the
volume of this solid?
B.95. Find the smallest whole number that
is divisible by all of the following numbers: 1, 2, 3, 4, 5, 6, 7, 8, 9,
and 10.
B.96. Find a positive whole number which
is the product of three consecutive whole numbers, and it is the product
of six consecutive whole numbers, also.
Please, send your solutions to: