ABACUS International Math Competition
for
3rd and 4th graders
March, 1998
A.49. What numbers would you write in the
empty fields? Why?
A.50. Which three numbers have a sum of
200?
A.51. In this addition same letters mean
same digits, different letters mean different digits. What number is 
?
A.52. How many eggs are there in a basket
if you would have 3 left over when taking them out of the basket in groups
of 5, you would have 4 left over when taking them out in groups of 7, and
you would have 5 left over when taking them out in groups of 9?
A.53. A triangle and a quadrilateral do
not have a side on the same straight line. How many mutual points can they
have on their borders the most?
A.54. Find four such whole numbers that
if you pick two of them in all possible ways and add those two numbers every
time, you get six consecutive whole numbers.
A.55. Find a few whole numbers so that
both their sum and their product should be 20.
A.56. In the number 7******9, replace the
six *'s by digits so that the sum of any three consecutive digits in this
number would be 20.
Please, send your solutions to:
Solutions of previous problems