Q&A - P5 Math

[tianzhu]

ftwm:

Ali has some singaore stamps, malaysia stamps & australia stamps in two albums. There were 765 stamps altogether. He moved 0.25 of the australia stamps, 0.6 of the malaysia stamps and 45 singapore stamps from the first album to the second album. He now found that there were 2 1/4times as many australia stamps as Malaysia stamps and 0.5 times as many Malaysia stamps as Singapore stamps in the first album. How many stamps did ali move from the first album to the second album?

Hi

Album A ----- after the transfer

Australia stamps -------- 9 units
Malaysia stamps -------- 4 units
Singapore stamps ------- 8 units

Album A ---- at first

Australia stamps -------- 12 units
Malaysia stamps -------- 10 units
Singapore stamps ------- 8 units + 45

30 units + 45 -------- 765

1 unit ------ 24

Number of stamps transferred from A to B -------- 3 units + 6 units + 45 ------ (9*24) + 45 ----- 261

Best wishes

[tianzhu]

Goodluck8:

At the meeting, there are 18 more women than men. The number of women is 45% more than the number of men. How many people were there at the meeting?
45% ---> 18
100 % ---> 40 people

Hi

Good Morning

45% ---> 18

5% ---> 2

100% ---> 40 men

Number of women ------- 58

Number of people ------ 58+40 ------ 98

Best wishes

[tianzhu]

Goodluck8:

Thanks Tianzhu

But i saw a similiar question in onsponge book

Hi Goodluck8

I am sorry.I made a mistake in my post this morning.

The total number of people ------ number of men + number of women.

Please refer to my revised post.

Best wishes

[tianzhu]

Goodluck8:

Another question:

In a class, there are 25% as many boys as girls. How many more girls than boys are there? Express your answer as a percentage?

Ans: 300%

Hi

Boys ----- 1 unit

Girls ----- 4 units

3/1*100% ------ 300%

Best wishes

[imacsg]

Can anyone help the below question. Thanks.


Lau purchased 5 similar rings and 3 similar watches for $695. Then he purchased 8 rings similar to the first 4 and had to pay $ 265 more than the cost of the 3 similar watches. Find the cost of the each ring?

What does they mean"smillar to the first 4"?

[MathIzzzFun]

imacsg:

Can anyone help the below question. Thanks.


Lau purchased 5 similar rings and 3 similar watches for $695. Then he purchased 8 rings similar to the first 4 and had to pay $ 265 more than the cost of the 3 similar watches. Find the cost of the each ring?

What does they mean\"smillar to the first 4\"?

Hi

I think there is a typo error in the question, I believe the question should read as:
Lau purchased 4 similar rings and 3 similar watches for $695. Then he purchased 8 rings similar to the first 4 and had to pay $ 265 more than the cost of the 3 similar watches. Find the cost of the each ring?

cheers.

[imacsg]

Hi MathIzzzFun,

Thanks for your reply. We will check with the teacher. if the question is as you mentioned.

Lau purchased 4 similar rings and 3 similar watches for $695. Then he purchased 8 rings similar to the first 4 and had to pay $ 265 more than the cost of the 3 similar watches. Find the cost of the each ring?

4R + 3W = 695
8R = 265 + 3W

12 R = 960
1 R = 80

So one ring is $80. Right.

[MathIzzzFun]

imacsg:

Hi MathIzzzFun,

Thanks for your reply. We will check with the teacher. if the question is as you mentioned.

Lau purchased 4 similar rings and 3 similar watches for $695. Then he purchased 8 rings similar to the first 4 and had to pay $ 265 more than the cost of the 3 similar watches. Find the cost of the each ring?

4R + 3W = 695
8R = 265 + 3W

12 R = 960
1 R = 80

So one ring is $80. Right.

bingo!

cheers.

[whywhy]

Hi Tianzhu, i need a simple method to do this St nick SA1 Q13.

Song Ren had a total of 50 coins. The coins were in denominations of 50ct, 20ct, & 5ct. He had an equal number of 50ct coins as 20ct coins. The total value of the 20ct coins & 5ct coins was $4.10. How many coins of each denomination did Song Ren have?

[tianzhu]

whywhy:

Hi Tianzhu, i need a simple method to do this St nick SA1 Q13.

Song Ren had a total of 50 coins. The coins were in denominations of 50ct, 20ct, & 5ct. He had an equal number of 50ct coins as 20ct coins. The total value of the 20ct coins & 5ct coins was $4.10. How many coins of each denomination did Song Ren have?

Hi

Good morning.

The total value of the 20ct coins & 5ct coins was $4.10.

$4 + 10 cents
$3.80 + 30 cents

Even value comes from the 20 cents coins and the odd amount from the 5 cents coins.

You may present your solution in a tabulated list similar to GC or “Assumption Method”. Try to establish a pattern.Here are some pointers.

$4 + 10 cents ------- 20 (20 cents coin) + 2 (5 cents coin) --------- 42 (20+20+2)

$3.80 + 30 cents ------- 19 (20 cents coin) + 6 (5 cents coin) --------- 44 (19+19+6)

Every increase of 20 cents (10 cents to 30 cents) leads to an increase of 2 coins (44-42)

50 - 42 ----- 8

8/2 ------ 4

Hence, we need 4 steps of an increase of 20 cents.

This gives 90 cents which is 18 number of 5 cents coin.

$3.20 + 90 cents ------ 16 (20 cents coin) + 18 (5 cents coin) --------- 50 (16+16+18)

5 cents ----- 18
20 cents ----- 16
50 cents ----- 16

Best wishes