Q&A - PSLE Math

[superksmum]

Hi MathIzzFun,


Really appreciate your help and explanation. Thank you so much.

Have a good night rest.

Cheers.

[MathIzzzFun]

aps:

Hi


Please help to solve this question:

Yanling had 60 % more stamps than Lena. Tricia had 75% fewer stamps tha Yanling. Yanling and Lena gave Tricia some stamps in the ratio 4:1. As a result, Tricia had 2 and a half times as many stamps as before and Yanling had 300 stamps more than Lena in the end. How many stamps did Lena give to Tricia?

Thanks!

Yanling : Lena --> 160 : 100 = 8 : 5
Yanling : Tricia --> 100 : 25 = 8 : 2
Yanling : Lena : Tricia = 8 : 5 : 2 --> 40u : 25u : 10u

After receiving stamps from Yanling and Lena,
Tricia --> 2.5 x 10u = 25u ---- she received 15u from Yanling and Lena
Yanling gave --> 4/5 x 15u = 12u
Lena gave --> 15u - 12u = 3u

In the end,
Yanling : Lena : Tricia --> 28u : 22u : 25u, Yanling had 300 more stamps than Lena

6u --> 300, 1u --> 50
Lena gave --> 150

cheers.

[oosh]

Hi,


Pls help to solve this question:

Jimmy and Tony drove 45Km from the library to the swimming pool. Tony started his journey 24mins later than Jimmy. Both of them reached the swimming pool at the same time. If Jimmy’s average speed was 50km/h, find Tony’s average speed (Ans: 90Km/h)

TIA

[oosh]

MathIzzzFun:

oosh:

Please help


Sean earns a% more than Alice. Cathy earns 30% less than Alice. If Alice earns $1500, what is the total amount of money earned by Alice, Cathy and Sean?
(Answer: $(4050 + 15a)

TIA

Alice --> $1500
Cathy --> 0.7 x $1500 = $1050
Sean --> (1+a/100) x $1500 = $1500 + 15a
Total --> $(4050+15a)

cheers.

Hi,

Thanks for your kind help. :salute:

[mujin]

oosh:

Hi,


Pls help to solve this question:

Jimmy and Tony drove 45Km from the library to the swimming pool. Tony started his journey 24mins later than Jimmy. Both of them reached the swimming pool at the same time. If Jimmy's average speed was 50km/h, find Tony's average speed (Ans: 90Km/h)

TIA

Jimmy : 50km/h = 50km/60min
45/50x60min = 54 min (jimmy travelled for 54 min)

Tony travelled for 54-24 min = 30 min

45km/30min = 45km/0.5h = 90km/h

[catddy2002]

Hi,


Pls help to solve these 2 questions:

1) At a party, there were some balloons, 40 balloons burst and 25% of the remaining ballons flew away. If only 2/3 of the balloons were left, how many balloons were there at first?

2) Jarmanye planned to cycle from Town A to Town B. If she cycled at 20km/h, she would reach Town B at 2 pm. If she cycled at 12 km/h, she would reached Town b at 3.30 pm. What was the distance between Town A and Town B?



Hi,

Pls assist in solving these 2 questions.
Thanks

Thanks

[oosh]

mujin:

oosh:

Hi,


Pls help to solve this question:

Jimmy and Tony drove 45Km from the library to the swimming pool. Tony started his journey 24mins later than Jimmy. Both of them reached the swimming pool at the same time. If Jimmy's average speed was 50km/h, find Tony's average speed (Ans: 90Km/h)

TIA

Jimmy : 50km/h = 50km/60min
45/50x60min = 54 min (jimmy travelled for 54 min)

Tony travelled for 54-24 min = 30 min

45km/30min = 45km/0.5h = 90km/h

HI,

Thanks so much. :grphug:

[oosh]

oosh:

Hi,


Needed some help on this question.

Jimmy runs 4km/h faster than he walks. He walks 1 1/2hr and runs the rest of the time over a distance of 6Km. If Jimmy walks as fas as he runs, find the amount of time he spends running.

Answer given = 1/2hr but my answer is 3/4hr. Will greatly appreciate any assistance.

Hi, appreciate any help :thankyou:

[atutor2001]

oosh:

oosh:

Hi,


Needed some help on this question.

Jimmy runs 4km/h faster than he walks. He walks 1 1/2hr and runs the rest of the time over a distance of 6Km. If Jimmy walks as far as he runs, find the amount of time he spends running.

Answer given = 1/2hr but my answer is 3/4hr. Will greatly appreciate any assistance.

Hi, appreciate any help :thankyou:

This is more like a test of English.

You have interpreted the sentence in red as \"distance which he ran = 6km\".

They have interpreted the sentence in red as \"Total distance = 6km\" i.e. distance which he ran = 3km.\"

I would pick your way of interpretation.

[jonaandr]

please help to solve the below 2 questions.


1. There were some balls in Boxes A,B and C. For every 3 balls in Box A, there were 7 balls in Box. For every 5 balls in Box B, there were 6 balls in Box C. After 48 balls were transferred from Box C to Box A, the ratio of the number of balls in Box A to the number of ball in Box B to the number of balls in Box C became 19:35:38. Find the total number of balls in the three boxes.

2. A motorcyclist travelle from Town A to Town B. It passed a taxi travelling from Town B to Town A. The taxi was traveling at a speed of 90 km/h. The motorcyclist reached Town B 1 1/2 hours after passing the taxi but the taxi was still 25 km away from Twon A. Both the motorcyclist and the taxi did not change their speeds throughout their journeys. If the motorcyclist took 4 hours to complete the shole journey, what was the distance between the two towns?

Thanks!