Tuesday, March 24, 2009
2. Mr Tan took 3 hours to cycle from town A to town B. He covered 4/9 of the journey in the first hour, 1/3 of it in the second hour and the rest in the third hour. Given that his average speed for the first two hours was 10.5km/h, find his average speed for the whole journey.
3. Simon completed a triath race in 3 hours 55 minutes. In the race, he swam, jogged and cycled at an average speed of 18km/h. Given that he swam 1km in 1 hour 30 minutesand took 5 minutes less to run 21 km, find:
(a) his cycling speed.
(b)the average speed at which he swam and cycled.
Give your amswers in km/h, in terms of fraction.
4.A train, travelling at 36 km/h, takes 37 seconds to pass through a 250-m tunnel. Travelling at the same speed, the train takes 28 seconds to pass through another tunnel. How long is the secong tunnel?
5.Peter drove at a constant speed of 40km/h from Village A to Village B to deliver some goods. Without spending anytime at Village B, he drove back to village A along the same route at a constant speed of 60km/h. In total, he took 5 hours to make the round trip. Find the distance between the two villages.
6.Eric cycled from home to school at an average speed of 15km/h. After school, his uncle drove him home at an average speed of 45km/h. Given that his trip back home took 1.8 hours less than his trip to school, find the distance between Eric's home and his school.
7.Mr Muthu is going to deliver some vegetables from the village to a market in town. If he cycles at an average speed of 10km/h, he will reach the market at 1p.m. If he cycles at an average speed of 15km/h, he will reach the market at 11a.m. What should his average cycling speed be if he wants to reach the market at 12 noon?
8.A dispatch rider has to deliver a parcel from City J to City S by a certain time.If he travels at an average speed of 90km/h,he will arrive at City S 1/2 hour late.What is the distance between the two cities?
9.Ah Seng walks to school at an average speed of 4km/h every day.One day,after walking a distance of 1 km,he realised that his watch was slow.So,he ran at a constant speed and managed to reach school just in time.Later,he calculated that if he had run at this speed right form the start of the journey,he would have reached school 5 minutes earlier.What was his running speed?
Monday, March 23, 2009
Friday, February 27, 2009
Answer Key
Section A (15 marks)
Question 1 to 5 (1 mark each)]
Question 6 to 15 (2 marks each)
Question | Answer | Question | Answer |
1 | 1 | 6 | 1 |
2 | 4 | 7 | 2 |
3 | 2 | 8 | 2 |
4 | 4 | 9 | 3 |
5 | 3 | 10 | 1 |
| | 11 | 4 |
| | 12 | 1 |
| | 13 | 3 |
| | 14 | 3 |
| | 15 | 3 |
Section B (20 marks)
Question 16 to 35 (1 mark each)
Question | Answer | Question | Answer |
16 | _{(a+6)} 2 | 26 | 2 |
17 | _{}5/3 or 1 2/3_{} | 27 | 3 |
18 | $72 | 28 | 42 |
19 | 2448 | 29 | $70m |
20 | C | 30 | 31.25% |
21 | 2 | 31 | 1.92m |
22 | 75% | 32 | 59 + c |
23 | 125 | 33 | $554 |
24 | | 34 | 70 |
25 | | 35 | 1 I 875 ml |
Section C (55 marks)
36. She had 2 3/5 kg of prawns left.
37. The ratio of the number of fiction books to the total number of books is 4 : 9.
38. (a) A
(b) D
39. $36 - $23 = $13
40. The total sum of money is $264.
41. The average number of stamps is (5x +5)/2 .
42. 71 game sets must be sold.43. 7200 pupils did not visit the zoo.
44. (a) Sunny had 768 stickers.
(b) Sunny had 408 more stickers than Rudy.
45. (a) The fraction is 9/10.
(b) Candy has 315 marbles.
Deborah has 350 marbles.
46. He had 21 swordtails at first.
47. The total amount raised was $37500.
48. (a) There were 1200 roses
(b) $2000 can be collected.
49. (a) There are 120 green apples.
(b) $102 can be collected.
50. He must sell 15000 books.
Monday, February 16, 2009
optical illusion
As promised here are some links for the optical illusion,http://www.optillusions.com/, http://www.eyetricks.com/illusions.htm
Wednesday, January 28, 2009
Maiden Blog
i've created a blog for us to keep each other updated with our daily activities in class. Feel free to drop a line or two.