MathCounts Countdown Round
How many CDs can Edward
buy for $14 each and spend the
same amount he would spend to
buy 60 CDs for $7 each?
30 CD's
What is the value of x if
3x + 7 = 22?
5
Tim’s math homework is on
five consecutive pages in the
math textbook, and the sum of
those page numbers is 630.
What is the page number of the
next page after these five
homework pages?
129
What is the probability that
a randomly selected two-digit
positive integer will be a
multiple of 11? Express your
answer as a common fraction.
1/10
If 1 = 3
2 = 3
3=5
4=4
5=4
then 6 = ?
3
A restaurant automatically
adds an 18% tip to the bill. If
the tip was $9, what was the
bill before the tip was added, in
dollars?
$50
The legs of a right triangle
measure 3/5 inches and 4/5 inches.
In inches, what is the length of
the hypotenuse?
1 (inch)
The integer 12,345 can be
expressed as the sum of two
prime numbers in exactly one
way. What is the larger of the
two primes in this sum?
12,343
Each of the 2898 students at
Descartes Middle School voted for
his or her favorite meal chosen
from a list of six different meals.
Pia created a circle graph to
represent the data. If a 60-degree
sector of the circle graph represents
votes for pizza, how many students
voted for pizza?
483 students
Using only an addition, how do you add eight 8’s and get the number 1000?
888 + 88 + 8 + 8 + 8 = 1000
A hummingbird flaps its wings 1500 times per minute while airborne. While migrating south in the winter, how many times during a 1.5-hour flight does the hummingbird flap its wings?
135,000
What is the greatest prime
factor of the difference 64^2 − 61^2?
5
The number 18 can be
written as the sum of nine
consecutive integers. What is
the product of these integers?
0
Five couples went to the
movies together. They all sit in
ten adjacent seats in the same
row. How many different ways
can they be seated if each
couple sits together?
3840 ways
What should come next in the sequence:
53,53,40,40, 27, 27
14
Sami’s Candy Store has six bins containing jellybeans. These bins contain 10, 13, 19, 8, 13 and 9 blue jellybeans. What is the mean number of blue jellybeans per bin?
12
John is 3 years older than
Peter. Ten years ago the sum of
their ages was 59. In years, how
old is John now?
41 years
How many distinct factors
of 25! are prime numbers?
9
Sun-Li sold candy bars for
the glee club for $0.50 each. If
she sold of the candy bars that
she had and has 12 candy bars
left, how many dollars has she
collected so far?
$18
If 72 x 96 = 6927, 58 x 87 = 7885, then 79 x 86 = ?
6897
When the positive integer x
is divided by each of 4, 5 and 6,
it has a remainder of 3. What is
the sum of the three smallest
possible values of x?
28
Five consecutive two-digit positive integers, each less than 30, are not prime. What is the largest of these five integers?
28
Sharon drives 30 mi at 60 mi/h
and 60 mi at 30 mi/h. What is
Sharon’s average speed, in miles
per hour, for the whole trip?
36 mi/h
In the game Yahtzee®, five
standard dice are tossed. What is
the probability that all five dice
show even numbers or all five
show odd numbers? Express
your answer as a common
fraction.
1/16
An oil tanker containing 108,000 gallons of oil releases 1/3 of its remaining volume every 2 hours. How many gallons remain in the tanker after 6 hours?
32,000