Q&A - PSLE Math

[MathIzzzFun]

stary:

stary:

Hi all,


Have a question...

Ali and Baba ran in a race. When Baba had completed the race, Ali had only run 5/8 of the distance. Baba's speed was 75 m/min faster than Ali's speed. Both of them did not change their speeds throughout the race.
What was Ali's speed in m/min?

Appreciate your help... :?

Someone help me!

Hi

Ratio of Baba’s speed to Ali’s speed
=Sbaba: Sali
= 8u: 5u

Difference in speed = 3u = 75m/min
1u = 25m/min

Ali’s speed = 5u = 5 x 25m/min = 125m/min

cheers.

[MathIzzzFun]

wkong:

Need help for the following question:-


Qn4


http://i56.tinypic.com/xfdd9k.jpg\">

Hi

http://i52.tinypic.com/161aijn.jpg\">

cheers.

[stary]

MathIzzzFun:

stary:

[quote=\"stary\"]Hi all,


Have a question...

Ali and Baba ran in a race. When Baba had completed the race, Ali had only run 5/8 of the distance. Baba's speed was 75 m/min faster than Ali's speed. Both of them did not change their speeds throughout the race.
What was Ali's speed in m/min?

Appreciate your help... :?

Someone help me!

Hi

Ratio of Baba’s speed to Ali’s speed
=Sbaba: Sali
= 8u: 5u

Difference in speed = 3u = 75m/min
1u = 25m/min

Ali’s speed = 5u = 5 x 25m/min = 125m/min

cheers.[/quote]Thanks MathIzzzFun!

[stary]

wkong:

stary:

[quote=\"wkong\"]Need help for the following question:-


Qn2

http://i51.tinypic.com/2q8d9bb.jpg\">

Unshaded/2 -> (1 - 1/4) / 2 = 3/8
1 rectangle -> 3/8 + 1/4 = 5/8
5/8 of figure ->5x 12 = 60 cm2
Figure -> 8/5 x 60 = 96 cm2

Thanks Stary.[/quote]Glad to help...

[tianzhu]

small:

Please help and many thanks in advance.


Question from a school paper:
Ben bought some bottles of glue for $20. He wanted to sell each bottle of glue for 40 cebts but only managed to sell 12 bottles. He then decided to lower the price and sold the remaining bottles for a total of $22.91.

(a) What was the lower price he sold each bottle for?
(b) How many bottles were sold at the lower price?

:?

Hi small

Good Morning.

What are the answers?

It looks like there is some missing information.

Best wishes

[pixiedust]

Would greatly appreciate some help with the following question. I need solution withOUT using Unit Transfer please.

Thank you :

Larry had some red and blue marbles in the ratio 2:5. After he bought another 30 red marbles and 15 blue marbles, the ratio became 4:7. How many marbles did Larry have at first ? Answer : 175 marbles

[lizawa]

pixiedust:

Would greatly appreciate some help with the following question. I need solution withOUT using Unit Transfer please.

Thank you :

Larry had some red and blue marbles in the ratio 2:5. After he bought another 30 red marbles and 15 blue marbles, the ratio became 4:7. How many marbles did Larry have at first ? Answer : 175 marbles

Red : Blue
= 2 : 5
(+30 red and + 15 blue)
= 2u + 30 : 5u + 15
= 4 :7

7(2u +30) = 4 (5u+15)
14u +210 = 20u +60
6u = 150
1u = 25
AT first -> 7u = 7 x 25 = 175.

[Brenda10]

pixiedust:

Would greatly appreciate some help with the following question. I need solution withOUT using Unit Transfer please.

Thank you :

Larry had some red and blue marbles in the ratio 2:5. After he bought another 30 red marbles and 15 blue marbles, the ratio became 4:7. How many marbles did Larry have at first ? Answer : 175 marbles

Hi pixiedust

Sorry, deleted as wrong post.

[pixiedust]

lizawa, thanks...but how to explain to P5/6 this step :

\"= 2u + 30 : 5u + 15
= 4 :7
7(2u +30) = 4 (5u+15)..\"

Brenda, no problem. If your dd has any other way to solve, do update too. thanks in advance.

[wkong]

MathIzzzFun:

Hi

http://i52.tinypic.com/161aijn.jpg\">

cheers.

Thanks again MathIzzzFun