Multiple Choice
A number is twice of another number. The average of the two numbers is 117. What is the larger number?
a) 39 b) 78 c) 156 d) 175
117 x 2= 234/3 x 2= 156
Luna reads an average of 16 pages of a book every day. How many pages will she read in 2 weeks?
16 x 14 = 224 pages
The average of seven numbers is 38. The sum of the first six numbers is 156. What is the seventh number?
a) 26 b) 110 c) 118 d) 266
38 x 7= 266
266 - 156 = 110 (b)
The average height of 15 boys is 1.52m. If one boy is 1m66cm tall, what is the average height of the other 14 boys?
15 x 1.52 = 22.8
22.8 - 1.66 = 21.14
21.14 / 14 = 1.51 cm
A van took 2 hours to travel from the office to a factory. If the distance between the two places is 92 km, find the speed of the van?
92 / 2 = 46km/h
Jenny has $12. Angela has $4 less than Jenny. Lily has $5 more than Angela. What was the average amount of money they had?
a) $7 b) $9 c) $11 d) $13
Jenny Unit +12
Angela Unit 12-4
Lily Unit 12-4+5
Jenny has 12, Angela has 8 and Lily has 13
12 + 8 +13 = 33/3 = $11
The average of two 3-digit numbers is 180.
First number 1 2 ?
Second Number 2 ? ?
What is the least possible number that the second number can be?
180 x 2 = 360
360 - 129 = 231
Second = 231
= 231
John Bai spent $36 on petrol to travel 300km in his car. If he traveled 12 km on 1 liter of petrol, what was the cost of 1 liter of petrol?
300/12 = 25 L Used
1L = 36/25 = $1.44
Sam filled 4 identical bottles with water. The average volume of water in each bottle was 0.85 L. What was the total volume of water in the bottles?
a) 3.2L b) 3.3L c) 3.4L d) 3.5L
0.85 x 4 = 3.4 L
These are the water charges for Dora in April.
Volume Rate
First 40 m3 $1.17 per m3
Above 40 m3 $1.40 per m3
She used 50 m3 in April. How much did she pay?
First 40m3 = 40 x 1.17
$46.8
Next 40-50 = 10 x 1.4
$14
46.8 + 14 = $60.8
Mr. Wong bought 2 chicken and 3 ducks. The total mass of the chickens was 4.05 kg and the mass of the 3 ducks was 900 g, 2.04 kg, and 4.13 kg respectively. What was the average mass of all the chickens and ducks altogether?
4.05 + 0.9 + 2.04 + 4.13 = 11.12 kg
11.2 /5 = 2.224kg
A rectangular tank measuring 40 cm by 30 cm by 60 cm contained 4.5 L of water. Water from Tap P flowed into the tank at a rate of 9L per minute. How long did it take to fill the tank?
40x30x60= 72,000 cm3
72 - 4.5 = 67.5 L67.5 L / 9 = 7.5 L
A crate of oranges is repacked into 5 boxes. The mass of the first box is 5.6kg. The total mass of the remaining boxes is 24.8kg. Find the average mass of the 5 boxes.
a) 6.2kg b) 6.08kg c) 5.9kg d) 5.85kg
5.6 + 24.8 = 30.4/5
6.08 (b)
These are the rates at a shopping mall.
First hour $3.00
Hour or part thereof $2.00
Mr Tang parked his car at the shopping mall from 3 p.m to 5.45 p.m. How much did he pay?
3-4 = $3
4-5 = $2
5-5.45 = $2
=$7
The average number of boxes that Justin and Juan carried from their storeroom to their office is 50 boxes each. On each trip, Justin carried 5 boxes while Juan carried 4 boxes. How many trips did Justin make if Juan made 10 trips?
50x2 = 100
Juan: 4 x 10 = 40 boxes
Justin: (100-40) / 5
60/5 = 12 trips
A rectangular tank 60 cm long, 60 cm wide and 40 cm high was 75% full of water. Water began to leak from a crack at the base of the tank 500 cm3 per minute. At the same time, water was also added into the tank from a tap at 3.5 L per minute. How long did it take the tank to fill the tank completely with water?
60 x 60 x 40 x 3/4 = 108,000
108 L
60 x 60 x 40 = 144,000
144 - 108 = 36L
3.5 - 0.5 = 3L
36 L / 3 L = 12min
Lynn's average score for 4 tests was 60. His score in the second test was twice his score in the first test. He scored 20 marks more in the third test than in the second test. He scored 70 marks in the fourth test. What was his score for the first test?
1st = 1 Unit
2nd = 2 units
3rd = 2 units +20
4th = a unit of 70
60 x 4 = 240
5 units = 240 - 90 = 150
150 / 5 = 30