Q&A - P3 Math

[concerned1970]

Hi! Can someone pls help me to solve all 3 ques? Ty in adv!


1) The sum of two fractions is 9/6. Their difference is 1/2. What is the smaller fraction?

2) Mrs Tan paid $171 for 5 books and 6 files. If 3 files cost the same as 2 books, how much did she pay for the books?

3) There are 60 more toy cars than dolls in a factory. 2/5 of the toy cars is equal to 4/7 of the dolls. How many toy cars are there in the factory?

[small]

HTH…


Q3) Mrs Tan paid $171 for 5 books and 6 files. If 3 files cost the same as 2 books, how much did she pay for the books?\t\t\t\t\t\t
\t\t\t\t\t\t\t\t\t
3 files cost the same as 2 books\t\t\t\t\t\t\t\t\t
6 files cost the same as 4 books\t\t\t\t\t\t\t\t\t
5 books and 6 files = 9 books\t\t\t\t\t\t\t

9 books = 171\t\t\t\t\t\t\t\t\t
1 book = 19\t\t\t\t\t\t\t\t\t

5 books = 5 x 19\t\t\t\t\t\t\t\t
\t = 95\t\t\t\t\t\t\t\t
\t\t\t\t\t\t\t\t\t
Mrs Tan paid $95 for the books

[small]

HTHS...


Q4

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[small]

HTh for Q2


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[concerned1970]

small:

HTH..


Q3) Mrs Tan paid $171 for 5 books and 6 files. If 3 files cost the same as 2 books, how much did she pay for the books?\t\t\t\t\t\t
\t\t\t\t\t\t\t\t\t
3 files cost the same as 2 books\t\t\t\t\t\t\t\t\t
6 files cost the same as 4 books\t\t\t\t\t\t\t\t\t
5 books and 6 files = 9 books\t\t\t\t\t\t\t

9 books = 171\t\t\t\t\t\t\t\t\t
1 book = 19\t\t\t\t\t\t\t\t\t

5 books = 5 x 19\t\t\t\t\t\t\t\t
\t = 95\t\t\t\t\t\t\t\t
\t\t\t\t\t\t\t\t\t
Mrs Tan paid $95 for the books

Hi! How do u get 9 books? Can u draw model diagram for me? Ty!

[Champion]

concerned1970:

small:

HTH..


Q3) Mrs Tan paid $171 for 5 books and 6 files. If 3 files cost the same as 2 books, how much did she pay for the books?\t\t\t\t\t\t
\t\t\t\t\t\t\t\t\t
3 files cost the same as 2 books\t\t\t\t\t\t\t\t\t
6 files cost the same as 4 books\t\t\t\t\t\t\t\t\t
5 books and 6 files = 9 books\t\t\t\t\t\t\t

9 books = 171\t\t\t\t\t\t\t\t\t
1 book = 19\t\t\t\t\t\t\t\t\t

5 books = 5 x 19\t\t\t\t\t\t\t\t
\t = 95\t\t\t\t\t\t\t\t
\t\t\t\t\t\t\t\t\t
Mrs Tan paid $95 for the books

Hi! How do u get 9 books? Can u draw model diagram for me? Ty!

Let me give a try :lol:
3 files = 2 books
6 files = 4 books

5 books (Draw a model of 5 units - take as 1 whole unit) + 6 files (Draw a model of 6 units - take as 1 whole unit) - $171
Therefore,
5 books, 1 whole unit = $171
5 books + 4 books = $171
9 books = $171

Therefore, the cost of 1 book is $171 / 9 = $19
5 books = 5 x $19 = $95

Sorry, I am very computer-retarded so I unable to draw out the model. Perhaps some other experts can assist you :imanangel:

[concerned1970]

Let me give a try :lol:

3 files = 2 books
6 files = 4 books

5 books (Draw a model of 5 units - take as 1 whole unit) + 6 files (Draw a model of 6 units - take as 1 whole unit) - $171
Therefore,
5 books, 1 whole unit = $171
5 books + 4 books = $171
9 books = $171

Therefore, the cost of 1 book is $171 / 9 = $19
5 books = 5 x $19 = $95

Sorry, I am very computer-retarded so I unable to draw out the model. Perhaps some other experts can assist you :imanangel:[/quote]

Oh thanks alot! I get it now!

[ttyh]

P3 Maths, pls help…


Using a 10cent coins, form a series of shapes with 1 coin on 1st row, 2 coins on 2nd row, 3 coins on 3rd row and so on.
i.e.

No. of rows No. of coins
1 ------- 1
2 ------- 3
3 ------- 6
4 ------- 10
5 ------- 15

How many 10 cent coins are needed to form 100 rows of coins?

(What is the forumla for thsi type of questions?)

[MathIzzzFun]

ttyh:

P3 Maths, pls help...


Using a 10cent coins, form a series of shapes with 1 coin on 1st row, 2 coins on 2nd row, 3 coins on 3rd row and so on.
i.e.

No. of rows No. of coins
1 ------- 1
2 ------- 3
3 ------- 6
4 ------- 10
5 ------- 15

How many 10 cent coins are needed to form 100 rows of coins?

(What is the forumla for thsi type of questions?)

Hi

1 row = 1
2 rows = 1+2 = 3
3 rows = 1+2+3=6
...
100 rows= 1+2+3+...+97+98+99+100=5050

cheers.

[tianzhu]

ttyh:

(What is the forumla for this type of questions?)

Hi

The formula is n(n+1)/2
The 100th term is 100(101)/2 which is 5050.

Best wishes