Q&A - PSLE Math

[fightingmom]

fightingmom:

tianzhu:

[quote=\"fightingmom\"]Hi,


Pls help in the working steps for following question from Rosyth SA1 2011 Q12:

Four children Min, Nathan, Tom and Caleb each have some savings. The amount of money Nathan has is 1/3 of the total amount of money Tom and Caleb have. The amount of money Tom has is 1/4 of the total amount of money Nathan and Caleb have. The amount of money Min has is 1/5 of the total amount of money Nathan, Tom and Caleb have. If Caleb saves $1035, how much do the four children have altogether ?
Ans: $2700

TIA

Hi

A similar question was discussed earlier.

Four children Min, Nat, Tom and Caleb each have savings. The amount of money Nat has is 1/3 of the total amount of money Tom , Min and Caleb have. The amount of money Tom has is 1/4 of the total amount of money Nat , Min And Caleb have. The amount of money Min has is 1/5 of the total amount of Nat, Tom and Caleb have. If Caleb saves $1035 . How much do the four children have altogether?

The total amount of money in the three scenarios is the same. Make the total number of units the same.

A common multiple of 4, 5 and 6 is 60.

Nat : (Tom + Min + Caleb) ------ 1:3 ((4) ------ 15:45 (60)
Tom : (Nat + Min + Caleb) ------ 1:4 (5) ------ 12:48 (60)
Min : (Nat + Tom + Caleb) ------ 1:5 (6) ------ 10:50 (60)

Nat ------ 15 units
Tom ------ 12 units
Min ------- 10 units
Caleb ------ 23 units

23 units ------ 1035
1 unit ------ 45

60*45 ------ 2700

Best wishes

Hi tianzhu,

Sorry can u explain why u add Min in the first 2 equation / ratio portion ?[/quote]
Hi tianzhu,

Ok I spotted the difference in your question posted and mine. I think the question sheet that I bought did not have Min in sentence 2 & 3. No wonder my DD and I can't solve it.

Thank you for the working steps!

[Michaelia0816]

7)Car x, car y and car z together crossed point a at noon as they were heading for point b. by 1.30 pm, car x was 75 km from point a and car y was ahead of car x by 6km. By this time, car x had already travelled the combined distance of the other two cars from point a. What was the difference in speed between car z and y?

[Michaelia0816]

the ratio of a van’s speed to that of a car’s speed was 3:5. If the van took 1 minutes more to cover a distance of 0.5 km than the car, find the speed of the van in km/h. ( hint: first convert 0.5 km/min to km/h)

[Michaelia0816]

9)A motorist took 3 h to travel from p to r while a cyclist took 5h20min to travel from s to q. If both of them set off at the same time, how far away from p did they pass by each other?

[Michaelia0816]

Roger took 1/1/3 h to drive from Greenland to pinkcity at an average speedof 0km/h. After this, he increased his speed by 25% and continued driving to redsville for 40 minutes.

A) how far did Roger drive together?
B) find his average speed for the whole journey?

[tianzhu]

Hi Michaelia0816


ah girl

Good Morning.

I observe you’re posting quite a number of questions.

Do you have difficulties solving them or just wanted to check the answers?

Best wishes

[Michaelia0816]

Peter set off from x for z at 10.45 am at a uniform speed of 64 km/h. 20 minute later, Dave set off from z to x at the uniform speed and he passed Peter at y.

The distance between x and y is 96km and the distance between y and z is 140km.
A) find the speed at which Dave was travelling?
B) at what time would Dave arrive at x?

[Michaelia0816]

tianzhu:

Hi Michaelia0816


ah girl

Good Morning.

I observe you’re posting quite a number of questions.

Do you have difficulties solving them or just wanted to check the answers?

Best wishes

Diffculties solving them! I just started on speed but my Cher had already given us a lot of hard question, to me only!

[Michaelia0816]

I still have have 13 question to post! So much question!

[tianzhu]

Michaelia0816:

Diffculties solving them! I just started on speed but my Cher had already given us a lot of hard question, to me only!

Hi

You mean those difficult questions were given to you only and not to other students.

Best wishes