2010 MATHEMATICS TEAMS CHALLENGE
Primary Relay
Time: 60 min
Calculators Allowed
100 points
-----------------------------------------------------------------------------------------------------------R1. (4 points)
[96 points remaining]
Coins numbered 1 – 100 are placed in a hat. What is the probability that a coin chosen at
random from the hat is a multiple of 6?
R2. (4 points)
[92 points remaining]
What is the largest two-digit number with the property that the sum of its digits is a prime
number?
R3. (6 points)
[86 points remaining]
What is the smallest three-digit number with the property that the sum of its digits is a
prime number?
R4. (2 points)
What is the next number in the sequence?
[84 points remaining]
1, 3, 6, 10, 15, 21, 28, 36,____
R 5. (4 points)
[80 points remaining]
Each year, Darren’s car is worth 10 percent less than it was the previous year. It is
currently worth $27,000. What was it worth one year ago?
R 6. ( 8 points)
[72 points remaining]
Sixty people, half of whom were females, were asked if they liked yogurt. Thirty-two of
the people, including two fifths of all the males, said they did like yogurt. How many of
the females didn’t like yogurt?
R 7. (4 points)
[68 points remaining]
Three consecutive whole numbers add to a total of 1,005. What is the smallest of theses
whole numbers?
R 8. (8 points)
[60 points remaining]
What is the right most digit (unit digit) of the following expression?
22010
R 9. (6 points)
[54 points remaining]
The exclamation point (!) is also used as a mathematical symbol, as in 5! (read as 5
factorial) in which 5! = 5 × 4 × 3 × 2 × 1 = 120 and 7! = 7 × 6 × 5 × 4 × 3 × 2 × 1 =
5,040.
What does 16! ÷ 13! Equal?
R 10. (4 points)
[50 points remaining]
How high can you stack a million ten dollar bills if each bill is 0.1 mm thick?
R 11. (6 points)
[44 points remaining]
What is the number?
It is between 100 and 900.
The sum of the digits is 14.
The sum of the hundreds digit and the tens digit equals the units digit.
The tens digit is one more than the hundreds digit.
R12. (6 points)
[38 points remaining]
For a social studies assignment, you are asked to read two of the six books on the list.
How many different sets of two books can you choose?
R 13. (6 points)
[32 points remaining]
Sonar measures the depth of water by using sound. The speed of sound in water is 1,497
metres/second. If it took 0.38 seconds for a sound to go from the surface of a lake to the
bottom and back. How deep was the lake at that point?
R 14. (8 points)
[24 points remaining]
Katelyn and Carly are playing a game. Each student has a set of five cards numbered 1 to
5. If Katelyn and Carly each turn over one card, what is the probability that the sum of
the two cards is even?
R 15. (2 points)
[22 points remaining]
A football stadium has 8,000 seats. At the first game, three times as many seats were
reserved for the home team. How many seats were reserved for the opposing team?
R 16. (4 points)
[18 points remaining]
One doughnut for each of 25 students will cost $3.75. If $6.00 is spent for doughnuts,
how many students can have a second doughnut?
R 17. (4 points)
[14 points remaining]
Miss Bacon’s family kept a record of her mobile phone calls for a 7-day period and found
that 63 calls had been made. At this rate, how many calls would she make in a 30-day
period?
R 18. (4 points)
[10 points remaining]
The National Fire Protection Association has established that it takes 5 seconds for each
person to pass safely through a revolving door. According to the National Fire Protection
Association, how many minutes would it take 60 people to pass safely through a
revolving door?
R 19. (6 points)
[4 points remaining]
What’s the greatest six-digit number you can write if each digit must be different and no
digit may be prime?
R 20. (4 points)
[0 points remaining]
What are the dimensions (side length in centimetres) of an ice cube that has a surface area
numerically equal to its volume?
Problem
R 1 (4 points)
R 2 (4 points)
R 3 (6 points)
R 4 (2 points)
Change
R 5 (4 points)
R 6 (8 points)
R 7 (4 points)
R 8 (8 points)
Change
R 9 (6 points)
R 10 (4 points)
R 11 (6 points)
R 12 (6 points)
Change
R 13 (6 points)
R 14 (8 points)
R 15 (2 points)
R 16 (4 points)
Change
R 17 (4 points)
R 18 (4 points)
R 19 (6 points)
R 20 (4 points)
MATHS TEAM CHALLENGE (2010)
Relay Answer Sheet
PRIMARY
Answer
Attempts √ or ×
Score Progressiv
8 7 6 5 4 3 2 1
e Score
16 4
,
𝑜𝑟 16%
100 25
98
101
45
Change
Change
$30,000
10 females
334
4
Change
Change
3,360
100 metres
347
15
Change
Change
284.43 m ≈ 284
13
, 0.52 or 52%
25
2,000
15 students
Change
Change
270 calls
5 minutes
986410
6 centimetres
Total
School:___________________________________
Team 1:
Team 2: