Q&A - P5 Math

[the shadowed snake]

hi all I was just wondering why use common factors to solve maths problems :siao: :siao:

[small]

the shadowed snake:

small:

[quote=\"the shadowed snake\"]Jack bought some pens and erasers for a total of $100.10. He spent $9.10 more on the pens than the erasers. Each pen costs $3.70 more than each eraser. Jack bought 6 times more erasers than pens. How much does each pen cost? Ans: 4.20

How to do.

Hi,

Please refer to mrswongtuition\"s solution.

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=69&t=280&hilit=Jerry+bought+four+times&start=480

thanks but i do not understand how she get Quantity of P:E is 1:7
P [__]
E [__][__][__][__][__][__][__]

Price of P & E (in total)
P [_______][_$9.10_] ````` } Total
E [_______] ````````````` }$100.10
this1:7 when the Q says 1:6 :scratchhead: :scratchhead: :scratchhead:[/quote]Hi,

The question mentioned 'Jack bought 6 times more erasers than pens.\"

[the shadowed snake]

Hi small I know but why does she put 1:7 in her working

:scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead:
I DO NOT UNDERSTAND STAND!

[small]

the shadowed snake:

Hi small I know but why does she put 1:7 in her working

:scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead:
I DO NOT UNDERSTAND STAND!

Hi,

Hope this help.

ratio 1 : 7 -----> 6 times more
ratio 1 : 6 -----> 6 times of

[Udon]

hi…hi…need help again!


Appreciate your help & time…

Q1. The ratio of Anna’s number of stamps to Lydia’s number of stamp was 5 : 8. The ratio became 3 : 7 when Lydia bought 55 new stamps. How many stamps do the two girls have altogether now?

[small]

Hi,


HTH..

Common lower multiple for 3 and 5 is 15

As number of stamps for Anna remains unchanged

At first:
Number of Anna's stamp to Lydia\"s stamps ----- 5:8 (15u:24u)

Now:
Number of Anna's stamps to Lydia's stamps ----- 3:7 (15u:35u)

35u - 24u ----- 55 stamps
11u = 55
1u = 5

Both girls have 50units of stamps altogether

50u ----- 50 x 5 = 250 stamps

[the shadowed snake]

small:

the shadowed snake:

Hi small I know but why does she put 1:7 in her working

:scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead: :scratchhead:
I DO NOT UNDERSTAND STAND!

Hi,

Hope this help.

ratio 1 : 7 -----> 6 times more
ratio 1 : 6 -----> 6 times of

:thankyou:

[Udon]

small:

Hi,


HTH..

Common lower multiple for 3 and 5 is 15

As number of stamps for Anna remains unchanged

At first:
Number of Anna's stamp to Lydia\"s stamps ----- 5:8 (15u:24u)

Now:
Number of Anna's stamps to Lydia's stamps ----- 3:7 (15u:35u)

35u - 24u ----- 55 stamps
11u = 55
1u = 5

Both girls have 50units of stamps altogether

50u ----- 50 x 5 = 250 stamps

How to get \"50 units\"? :?
\"Both girls have 50units of stamps altogether\"

[small]

My apologies, it should be Anna and Lydia have 50u altogether.


Now
Anna's stamps ----- 15u
Lydia's stamps ----- 35u

Total stamps ----- 50u

1u = 5
50u ----- 50 x 5 = 250 stamps.

[Udon]

Hi,small

:thankyou: very much