Mathletics 2013

Seniors – Grades 7 & 8Session 2

TV & Entertainment Logic

Cartoons Environment

10 20 30 5040 10 20 30 5040

10 20 30 5040 10 20 30 5040

Q1. Mario’s Obstacles

Answer

O = 3M + 18O = number of obstacles M= number of Monsters Mario has killed.If Mario has killed 4 monsters, what is O ?

Q2. Amazing Race

22 Episodes recordedRory watches 2 episodes every 3 daysHow many days to complete 22 episodes ?

Answer

Q3. Juno Awards

In 2011, 1.8 million watchedIncreased by 10% in 2012Decreased by 10% as compared to 2012 in 2013.How many people watched in 2013 ?

Answer

Q4. Disney’s Jessie

2009 premiere aired on Sept 11th

June 11 2009 was a Thursday.What day of the week was Sept 11th 2009.

Answer

Answer

Alex wants to organize a party.

She has two options for food:

1.Buffet: $24/guest + 2 waitpersons

2.Catered: $30/guest + 8 waitpersons

Each waitperson charges $50.

She has two options for music:

1.DJ: $80/h2.Band: $325

There are 50 guests, and the party lasts 4 hours.

What is the cheapest option?A) Buffet & DJ C) Catered & DJ

B) Buffet & Band D) Catered & Band

Q5. Wizards’ Party

Q1. Robbery!

Diamond stolen.Jack: I did not do that.Mike: Jerry is the criminal.Jim: Mike stolen the diamond.Jerry: I am not criminal.One of the four suspects was lying.Who is the criminal ?

Answer

Q2. Coke CansCoca Cola launched a sales promotion. If you buy 2 cans of Coca Cola, you can get one for free when you return the two empty cans.The price is one dollar per can. You have $20 How many cans can you get?

Answer

Q3. Teacher Age

Principal is 50 to 70 years oldTeacher’s age is 5/9 of PrincipalTeacher’s age is divisible by 2.Assume both ages are integer numbersHow old is teacher ?

Answer

Q4. Lighter Ball

There are 12 ballsOne is lighter than the restHow many times do you have to weigh to find the lighter ball ?

Answer

Q5 Containers

5 & 6 Litre ContainersHow many litres total are needed to measure 2 litresFill-Pour Measurement: Fill the container fully with 6 litres of water and pour into the 5-litre container, the water left in the 6-litre container is 1 litre. Continue this method…

5 Litres

6 Litres

Answer

Q1. Dexter’s ExperimentDexter is doing a science experiment and needs 200 mL of water. He needs to mix this in a huge vat with 2 mL of dye and 7 full cans of his super-secret glue formula (which each hold 125 mL). He wants to transfer all of the solution into 0.25 L bottles for easier transportation. How many bottles does he need?

Answer

Q2. Ninja Turtle PizzaThe Ninja Turtles love pizza. The local pizza parlour makes large pizzas that are 10 slices to a (pizza) pie. They can also top them so that, if you wanted, you could get different toppings on each slice. The first slice Donatello ordered had one topping on it. On the next four slices, Michelangelo had 2 toppings. Raphael then ordered 3 toppings on the next seven slices. How many pizzas in total to get to 7 toppings on a slice if they continue to order like this? Answer

2 toppings

1 topping

3 toppings

Q3. Scooby-Doo’s SignShaggy and Scooby-Doo painted a new rectangular sign with a multicolour design. They then tacked it up on a wall using nails spaced 5 cm apart, making sure they had exactly one nail in each of the four corners. If they used 13 nails on the left side, and 90 nails in total, how big was the sign? Answer in square centimetres. Answer

Shaggy and Scooby-Doo

Adventure Sign!

13 nails

Q4. Jetsons’ Aerocar TripThe Jetsons are planning a trip in their aerocar to visit the famous Astro Tower in Sun City. It is 1632 km away from their home in Orbit City. Their aerocar uses 2 L of fuel for every 8 km, and the tank only holds 10 L of fuel. How many times will they have to fill up their tank? (Note: A partial fill is still considered a fill.)

Answer

Q5. Flintstone Record Room

Fred Flintstone is building a new cylindrical room to store his record collection.

The room must have an inner diameter of 10 ft.

It also has to be 12 ft tall.

To make sure his pet Dino doesn’t accidentally knock anything over, the walls must be 2 ft thick.

If he also put a roof of the same thickness as the walls on top of the structure, how much stone does he need in total to build the new room? Round answers to the nearest ft3. Answer

Q1. Hot & Cool Days

Answer

Tuesday’s high temperature was 4° C warmer than that of Monday’s. Wednesday’s high temperature was 6°C cooler than that of Monday’s. If Tuesday’s high temperature was 22°C, what was Wednesday’s high temperature?

(A) 20°C (B) 24°C (C) 12°C (D) 32°C (E) 16°C

Q2. Tree Planting

Answer

Steve plants ten trees every three minutes. If he continues planting at the same rate, how long will it take him to plant 2500 trees?

(A) 1 ¼ h (B) 3 h (C) 5 h (D) 10 h (E) 12 ½ h

Q3. Recycling TruckYour community is very environmentally friendly and each home recycles enough materials each week to fill two recycling bins.  If a recycling truck works 10 hours in one day and can stop at 60 houses in one hour, how many recycling bins can they collect in one day?

Answer

Q4. Compost ProgramYour community is considering a compost program for food waste.Community has a population of 73,000 people Each person creates 25.4kg of waste each week. Of this waste, 10% is food waste. How much food waste is created per week that could be diverted from the landfill (mass in kg)?

Answer

Q5. Snow Fall

Snow is falling at a rate of 1 mm every 6 minutes. A one metre cubic box is placed in the open to collect the snow.Snow fell for 1 hourIf one cubic meter of snow weighs 500 Kg, what is the weight of snow collected after 1 hour ?

1m

1m 1m

Answer

Mario’s Obstacles

Answer: 30 obstaclesO = 3 * M + 18M = 4Therefore O = 3 * 4 + 18 = 30

Main Page

Amazing Race

Answer: 33 days2/3=22/n, n=number of daysn=22*3/2n=66/2n=33

Main Page

Juno Awards

Answer: D (1.782 million)10% increase from 1.8 million is

1.8+(10*1.8/100) =1.9810% decrease from 1.98 is 1.98 - (10*1.98/100) = 1.782 million

Main Page

Disney’s Jessie

Answer: ANumber of days from June 11 to Sep 11 is 92.If you divide 92 by 7 (92/7)gives a remainder of 1. So September 10 is a Thursday and September 11 2009 is a Friday.

Main Page

Answer: A (Buffet & DJ)Solution:Food:Buffet: $24/guest X 50 guests + 2 waitpersons X $50 =

$1200+$100 = $1300Catered: $30/guest X 50 guests + 8 waitpersons X $50 =

$1500+$400 = $1900

Music:DJ: $80/h X 4 hours = $320Band: $325

Main Page

Wizards’ Party

Robbery

Answer: B (Mike)Mike and Jim’s statement are conflicting. Either one of them is saying the truth. If Jim is lying, Mike is saying the truth which means Jerry is lying (which is not possible). So Mike is lying and all others are saying the truth.Mike is the criminal

Main Page

Coke CansAnswer: 39 Cans

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20

21 22 23 24 25 26 27 28 29 30

31 32 33 34 35

36 37

38

39

Main Page

Teacher’s Age

Answer: 30 yearsBoth principal and teacher's ages are integers. There are only two numbers between 50 and 70 that can be divided by 9, which are 54 and 63 (since teacher’s age is 5/9 of principal). The age of the principal can be either 54 or 63. Therefore the teacher may be 30 years old or 35 years old. Because the teacher's age is evenly divisible by 2, the answer is 30 years old.

Main Page

Lighter Ball

Answer: 3 timesBalance 6 balls on one side and 6 on the other

side. Put the heavier 6 balls away. Using the 6 lighter balls, balance three Balls on

each side. Take lighter 3 balls.Choose any two of the lighter three balls, put one

in each side. If they are balanced, the one left out is the lighter

ball. If they are not balanced, you can pick out the lighter ball.

Main Page

Containers

Answer: 12 litres1. Fill B full (6 L), pour into A, then there is 1

L of water left in B. Empty A and pour the water from B to A. (So you have 1 L in A and nothing in B.)

2. Fill B full (6 L), pour into A until A is full. This means that 5-1=4 L of water have been poured into A. And then there 6-4=2 L of water left in B. So you need 12 L total to measure 2 L of water with these pails.

Main Page

Dexter’s ExperimentAnswer: 5Solution:

Total amount of liquid = water + dye + glue= (200 + 2 + 7*125) = 1077 mLVolume of a bottle = 0.25 L*1000 = 250 mLNumber of bottles = 1077/250 = 4.3 (round up) = 5 bottles

Note: You can’t have only part of a bottle! You either use it or you don’t. So the correct answer is 5.

Main Page

Ninja Turtle Pizza

Answer: 7Solution:

Sequence:

Total number of slices: 1 + 4 + 7 + 10 + 13 + 16 + 19 = 70Total number of pizzas: slices/10 = 70/10 = 7

Main Page

Toppings

1 2 3 4 5 6 7

Slices 1 4 7 10 13 16 19

Scooby-Doo’s SignAnswer: 9900 cm2

Solution:There are 13 nails per side, so this means there are 12 spaces (between nails) on each side. 12 x 5 = 60 cmOn top and bottom (not including the corners), there are 90 – (2*13) = 64 nails 64 / 2 = 32 nails on top edgeIf the corners are included, there are 32+ 2 = 34 nails on the top, and 33 spaces between the nails. 33 x 5 = 165 cmArea = length x width = 165 cm x 60 cm = 9900 cm2

Main Page

Jetsons’ Aerocar Trip

Answer: 41Solution:

Amount of fuel used = 1632 km * (2 L / 8 km) = 408 LNumber of fill-ups = 408 L / 10 L = 40.8 (round up) 41

Main Page

Flintstone Record Room (1)

Answer: 1212 ft3

Solution:The volume of the walls can be calculated by taking the

bigger cylinder (outer wall) and subtracting the smaller cylinder shape (inner room).

Let r be the radius of the inner room,and R be the radius of the outer part of the wall.

V room = πr2h = (3.14)(5)2(12) = 942 ft3

V outer wall = πR2h = (3.14) (7)2(12) = 1846 ft3

V walls = V outer wall – V room = 1846 – 942 = 904 ft3

Continued…

Flintstone Record Room (2)

The roof is also a cylinder, with a radius that is the same as the outer wall. Its height is the thickness of the wall (i.e. 2 ft).

V roof = πR2h = (3.14) (7)2(2) = 308 ft3

V total = V walls + V roof = 904 + 308 = 1212 ft3

Main Page

Hot and Cold Days

Answer: C (12°C) If Tuesday’s temperature was 22°C

then Monday’s high temperature was 18°C.

Wednesday’s temperature was 12°C since it was 6°C cooler than that of Monday’s high temperature.

Main Page

Tree Planting

Answer: E (12 ½ hours)

Since Steve plants ten trees every three minutes, he plants one tree every 3/10 minute.In order to plant 2500 trees, he will need

3/10 minute/tree × 2500 tree = 750 minutes There are 60 minutes in an hour, so

750/60 = 12 ½ hours.

Main Page

Recycling Truck

Answer: 1200 bins 2 bins/house x 60 houses/hour x 10

hours/day = 1200 bins

Main Page

Compost Program

Answer: 185,420 kg73,000 people25.4 kg/person/week 10% of it is food wasteSo total is 73,000 X 25.4 X 10/100 = 185,420 kg

food waste per week for compost

Main Page

Snowfall

Answer: 5 kgSince 1 mm of snow falls every 6 minutes, 10 mm

would have fallen after 60 minutes (1 hr)10 mm = 0.01 m

Total volume of box = 1 X 1 X 1 = 1 m3

Volume of snow after 1 hr = 1 X 1 X 0.01 m = 0.01 m3

Weight of 1 m3 of snow = 500 kgTherefore, weight of 0.01 m3 of snow = 500 X 0.01

= 5 kg

Main Page