Q&A - PSLE Math

[tianzhu]

Chan09:

Mgs 2011:

Distance between A and B is116km. The bus left A and headed for B. some time later a car left A and headed B along same route. Along the way the car overtake the bus and arrive at B, 45 minutes earlier than the bus. When the car arrived at B,the bus had travelled 5/8 of the distance. What was the speed of the bus?

I had 36.25 km/h though not sure if this is right?

Hi

For Speed question, it’s useful to start with a simple diagram.

116/8 ------ 14.5

14.5*3 ------- 43.5

Speed of bus ------- 43.5*(4/3) -------58 km/h

Best wishes

[2DMommy]

Please help me with this question :


Keane bought some marbles and gave half of them to Leon. Leon bought some stamps and gave half of them to Keane.

Keane used stamps and Leon gave away marbles. The ratio of the number of stamps to the number of marbles Keane had left then became 1 : 7 and ratio of the number of stamps to the number of marbles Leon had left became 1 : 5.
How mnay stamps did Leon buy ?

Thanks !

[MathIzzzFun]

2DMommy:

Please help me with this question :


Keane bought some marbles and gave half of them to Leon. Leon bought some stamps and gave half of them to Keane.

Keane used stamps and Leon gave away marbles. The ratio of the number of stamps to the number of marbles Keane had left then became 1 : 7 and ratio of the number of stamps to the number of marbles Leon had left became 1 : 5.
How mnay stamps did Leon buy ?

Thanks !

Hi

http://tinyurl.com/mathizzzfun-Cx-UP-1205-01

cheers.

[2cor41618]

2DMommy:

Please help me with this question :


Keane bought some marbles and gave half of them to Leon. Leon bought some stamps and gave half of them to Keane.

Keane used stamps and Leon gave away marbles. The ratio of the number of stamps to the number of marbles Keane had left then became 1 : 7 and ratio of the number of stamps to the number of marbles Leon had left became 1 : 5.
How mnay stamps did Leon buy ?

Thanks !

Hi, did u miss out some info on the highlighted part?

[sleepyqueen]

2cor41618:

2DMommy:

Please help me with this question :


Keane bought some marbles and gave half of them to Leon. Leon bought some stamps and gave half of them to Keane.

Keane used 5 stamps and Leon gave away 11 marbles. The ratio of the number of stamps to the number of marbles Keane had left then became 1 : 7 and ratio of the number of stamps to the number of marbles Leon had left became 1 : 5.
How mnay stamps did Leon buy ?

Thanks !

Hi, did u miss out some info on the highlighted part?

Updated the question

[ruohoo97]

Mrs Yeo bought some cakes for her class pupils. the girls received twice as many as the boys. There were an equal number of girsl and boys in her class. Each boy ate 4/7 of a cake and they finished all the cakes that were given to them. Each girl ate 1/3 of a cake and they had 8 and 1/2 cakes left. How many cakes did Mrs Yeo buy?


Thanks in advance!

[tianzhu]

ruohoo97:

Mrs Yeo bought some cakes for her class pupils. the girls received twice as many as the boys. There were an equal number of girsl and boys in her class. Each boy ate 4/7 of a cake and they finished all the cakes that were given to them. Each girl ate 1/3 of a cake and they had 8 and 1/2 cakes left. How many cakes did Mrs Yeo buy?


Thanks in advance!

Hi

Would you like to share where is this question from?

I have an answer of 18 cakes.

However, I find it a bit strange, if you try to find the number of boys, you’ll end up with not a whole number.

Do you have the answer from the WS?

Best wishes

[ruohoo97]

Yes, I find it strange too. It’s from ACSJ P6 2

SA1, 2011. I don’t have standard answer as it was given by my DD’s teacher for this June holiday homework.

[Michaelia0816]

Need help with those following hard question, from practice paper!


1) 10 cooks working for 8 hours each, can prepare a meal for 160 people. How many cooks will be needed to prepare a meal for 220 people if they are required to prepare in 5 hours?

[Michaelia0816]

2) In an army camp of 1200 men have sufficient rations for 25 days at the rate of 2400g per man per day. If 300 men join, and the rations are reduced to 2000g per man per day. How long will the food last all of them?