Category Archives: MATHCOUNTS

Amy, Bob, Charlie, David and Emily took part in a math exam. Their average score was 85. After checking his answer sheet against the answer sheet, Amy found that her score was wrong and reported it to her teacher. After … Continue reading →

Kevin was calculating the product of two numbers. One of the numbers is 78. However, instead of using 78, he was using 87 and the result was off by 45. The other number used in multiplication is __________. The sum … Continue reading →

Black stones and white stones are arranged on the table in the following pattern: ⚫◯◯⚫⚫⚫◯⚫⚫◯◯◯⚫◯◯⚫⚫⚫◯⚫⚫◯◯◯⚫◯◯⚫⚫⚫ …… The color of the 999th stone is __________ and there are ____________ white stones among the 999 stones. For the following sequence of numbers: … Continue reading →

The total number of 2-digit positive integers with the ten-digit greater than the unit-digit is __________. The sum of 20 consecutive natural numbers is 2010. The smallest one is __________ and the largest one is __________. The following are rows … Continue reading →

Use symbol $+$, $-$, $\times$ and $\div$ to fill in the blanks to make the following equation: $$ \texttt{1}\ \boxed{　}\ \texttt{2}\ \boxed{　}\ \texttt{3}\ \boxed{　}\ \texttt{4}\ \boxed{　}\ \texttt{5}\ =\ \texttt{20}$$ Find the value of the following: $$9999999+999999+99999+9999+999+99+9$$ Find the value of … Continue reading →