Q&A - PSLE Math

[skvn]

pls help to solve.
A bought three times as many notebooks as storybooks and spent a total of $186. he spent $42 more on the storybooks than the notebooks. Given that a storybook cost $9 more than a notebook, find the cost of a notebook.

thank you.

[Kangkangteo]

pls help to solve.
A bought three times as many notebooks as storybooks and spent a total of $186. he spent $42 more on the storybooks than the notebooks. Given that a storybook cost $9 more than a notebook, find the cost of a notebook.

thank you.

3 Nu + 1 Su ----> $186

1 Su - 3 Nu -----> $42

2 Su ----> 186 + 42 = 228
1 Su -----> 228/2 = $114

3 Nu ----> 186 - 114 = 72
1 Nu ----> 72/3 = $24

1 Su - 1 Nu ----> 114 - 24 = $90

90/9 = 10 items in each unit

24/10 = $2.40

Each notebook cost $2.40.

[guchengyouzi]

Hi guzhengyouzi

I think you have a typo, should be 35 , not 36

20%(u -35).....

Thanks.
Amended liao

[speedmaths.com]

pls help to solve.
A bought three times as many notebooks as storybooks and spent a total of $186. he spent $42 more on the storybooks than the notebooks. Given that a storybook cost $9 more than a notebook, find the cost of a notebook.

thank you.

Hi,

This question is similar to the one below:


Question:

Peter bought some items to sell at a carnival. 3/5 of the items were key chains and the rest were mugs. He spent a total of $520 on all the items. In total, he spent $280 more on mugs than on key chains. Given that each mug cost $8 more than each key chain, what was the cost of each mug?


Solution:

(He spent a total of $520 on all the items.)
(He spent $280 more on mugs than on key chains.)

Total Cost of mugs is ($520 + $280) / 2 = $400
Total Cost of key chains is ($520 - $280) / 2 = $120


(3/5 of the items were key chains and the rest were mugs.)

He bought 3 Boxes of key chains
He bought 2 Boxes of mugs.


2 Boxes of mugs cost $400
1 Box of mugs cost $200


3 Boxes of key chains cost $120
1 Box of key chains cost $40


Difference between the cost of 1 Box of mugs and 1 Box of key chains is ($200 - $40 =) $160

Difference between the cost of 1 mug and 1 key chain is $8

Number of items in 1 Box is $160 / $8 = 20 (mugs / key chains)


1 Box of mugs cost $200
20 mugs cost $200
1 mug cost $10


Hope this helps

Cheers



speedmaths
.

[AbiSuresh]

At a swimming meet, school A had 18 more representatives than school B and 6 fewer representatives than school C. The ratio of boys to girls from the three schools was 1:3. The ratios of boys to girls in schools A B and C were 1:3, 1:5 and 2:5 respectively. How many representatives from the 3 schools were there in all

[Kangkangteo]

At a swimming meet, school A had 18 more representatives than school B and 6 fewer representatives than school C. The ratio of boys to girls from the three schools was 1:3. The ratios of boys to girls in schools A B and C were 1:3, 1:5 and 2:5 respectively. How many representatives from the 3 schools were there in all

School A --- B : G = 1 : 3 (already same as that in schools A. b and C)

So now make sure that ratio of boys to girls in schools B and C should be 1 : 3 (or 2 : 6,etc. ... In this case it is 5 : 15)

School B ---- B : G = 1 : 5

School C ----- B : G = 2 : 5 = 4 : 10

Number of representatives from C - that from B = 18 + 6 = 24

So (4+10) - (1+5) = 8u -----> 24

1u ---> 24/8 = 3

B ----> 6 x 3 = 18

C ----> 14 x 3 = 42

A ----> 42 - 6 = 36

18 + 42 + 36 = 96

There were 96 representatives from the three schools in all.

[zinmkw]

Please help following question from RGS 2013, thanks in adv
Town A and Town B are are 420 km apart. At 9 am, a truck left Town A for Town B, travelling at an average speed of 40 km/h. At 10.30 am, a car left Town A for Town B, travelling at an average speed of 60 km/h. At the same time when the car overtook the truck, a cyclist left Town B and cycled toward Town A at an average speed of 30 km/h.

(a) At what time did the car catch up with the truck on the way to Town B?

(b) At what time would the cyclist meet the car along the way?

[chloe_]

Dear all

Need some help, thanks a lot!

Max walked from his home to school. For the first 2 minutes, he was walking at an average speed of 50m/min. When he realised that he was going to be late by 5 minutes, he quickly increased his speed by 20m/min. In the end, he was early by 3 minutes. Find the distance between his home and the school.

[Kangkangteo]

Please help following question from RGS 2013, thanks in adv
Town A and Town B are are 420 km apart. At 9 am, a truck left Town A for Town B, travelling at an average speed of 40 km/h. At 10.30 am, a car left Town A for Town B, travelling at an average speed of 60 km/h. At the same time when the car overtook the truck, a cyclist left Town B and cycled toward Town A at an average speed of 30 km/h.

(a) At what time did the car catch up with the truck on the way to Town B?

(b) At what time would the cyclist meet the car along the way?

40 x (T + 1.5) = 60 x T
20 T = 40 x 1.5
T = 3 h

10.30 a.m. 3h. 1.30 p.m.
|---------------------------|

a) the car caught up with the truck at 1.30 p.m.

60 + 30 = 90 km/h

60 x 3 = 180 km

420 - 180 = 240 km

240/90 = 2 2/3 h = 2 h 40 min

1.30 p.m. ..2 h 30 min ...4 p.m. ...10 min ....4.10 p.m.
|---------------------------|-----------------------|

B) The cyclist met the car at 4.10 p.m.

[Kangkangteo]

Dear all

Need some help, thanks a lot!

Max walked from his home to school. For the first 2 minutes, he was walking at an average speed of 50m/min. When he realised that he was going to be late by 5 minutes, he quickly increased his speed by 20m/min. In the end, he was early by 3 minutes. Find the distance between his home and the school.

50 x 2 = 100 m

D/50 = T + 5

D/(50+20) = T - 3

D/50 - D/70 = 5 + 3
D = 1400 m

1400 + 100 = 1500m (or 1.5 km)

The distance between his home and the school was 1.5 km.