Tutor MathsGuru: Ask me for your burning Maths questions!

[Dharma]

acehkr3009:

Hi all,


I have a question here and my solution, but not too sure if method is appropriate for Pri level and if answer is correct. Need some feedback.

1/3 of the flowers in a park were Roses and the rest Hibiscus. 3/4 of the Roses were pink and the rest were red. 5/8 of the Hibiscus were red and the rest were pink. There were 156 pink flowers. How many flowers were there in the park?

1/3 Roses, 2/3 Hibiscus
3/4 of Roses are pink & 3/8 ( 1 - 5/8 ) of Hibiscus are pink

Fraction of pink Roses -> 1/3 x 3/4 = 1/4
Fraction of pink Hibiscus -> 2/3 x 3/8 = 1/4

Fraction of pink flowers -> 1/4 + 1/4 = 1/2

If 1/2 -> 156
2/2 -> 2 x 156 = 212

Total there is 212 flowers in the park

Hi,

You workings are fine but the answer is 312

[blessedami]

acehkr3009:

Hi,


Here is another part whole question....

3 women donated some money to charity. The amount Alice donated was 1/4 the amount donated by Betty and Candy. The amount Candy donated was 1/2 the amount donated by Alice and Betty. Betty donated $250 more than Candy. How much was donated by all the 3 women?

I can used simultaneous equation to solve, but dont think my children can understand. Pls advise other ways for Pri level. Thanks.

Thanks

Hi,

This is how my DS worked it out:

A:B+C
1:4

C:A+B
1:2

Since the total is constant, we must find the LCM of ( 1+4 ) and ( 1+2 )

which is : 15

So, the ratio will become
A: B+C
3 :12

A+B
5: 10

So, Alice donated 3 units, Candy donated 5 units and therefore, Betty donated 7 units.

7u - 5u = 2u
2u---> $ 250
So, 15u----> $250 /2 x 15 = $ 1875

[Dharma]

acehkr3009:

Hi,


Here is another Part whole question....

A farm had pigs, goats and cows. 2/5 of the total number of animals in the farm were cows. 3/5 of the goats and twice as many cows were sold. 45 animals were sold. How many cows were left if there were 38 pigs?

Pls help on this question. Thanks.

Cows : 2u
Goats & Pigs : 3u

(3/5 + 6/5) of goats = 45
9/5 of goats = 45
1/5 of goats = 5
Total no. of goats = 25

3u = 25 + 38 = 63
1u = 21
Total no. of cows = 2u = 42
Total no. of cows sold = 6/5 x 25 = 30
Total no. of cows left = 42 – 30 = 12

[Dharma]

acehkr3009:

Hi,


Here is another part whole question....

3 women donated some money to charity. The amount Alice donated was 1/4 the amount donated by Betty and Candy. The amount Candy donated was 1/2 the amount donated by Alice and Betty. Betty donated $250 more than Candy. How much was donated by all the 3 women?

I can used simultaneous equation to solve, but dont think my children can understand. Pls advise other ways for Pri level. Thanks.

Thanks

Alice : 1/5
Candy : 1/3
Betty = 1 – 1/5 – 1/3 = 7/15

7/15 – 1/3 = 2/15
2/15 => $250
15/15 => $1875 (Total amt spent by the 3 girls)

[Almighty]

tianzhu:

Dharma:

Hi Dharma

Yes, how one cuts out the block (44*36*24) affects the surface area of the remaining block.

I am not sure if the question from the TS is reproduced exactly from the source or it has been summarised. How the question is worded has direct bearing on the answer.

If how the block is cut out is not expressly worded in the question, then one should go for the L shaped remainder which is easier to calculate the surface area.

Best wishes

Hi Tianzhu,
I had worded exactly as how it was in my source. Sorry to reply late.Just saw yr quote.
Thankyou Dharma n tianzhu 4 the g8t help...

[Carrot]

hi

tough question here pleasee help

john shifted the decimal point onumber twice to the left to obtain a new number. the difference between thr new number and the original number was 136.62
a) How many times of the new number is the original number?
b) What is the sum of the 2 numbers ? :scratchhead: :stupid:

[maths6a]

Carrot:

hi

tough question here pleasee help

john shifted the decimal point onumber twice to the left to obtain a new number. the difference between thr new number and the original number was 136.62
a) How many times of the new number is the original number?
b) What is the sum of the 2 numbers ?

To better understand this question, take 100 as the original number. When you move its decimal place to the left 2 places, the number becomes 1.
so the original number is 100 units and the new number will be 1 unit.
The sum between the 2 numbers will be 101 units and the difference between them will be 99 units.

a) the new number is 100 times the new number.

99 units --- 136.62
101 units --- 101 x 136.62 /99
= 139.38

[tianzhu]

maths6a:

99 units --- 136.62
101 units --- 101 x 136.62 /99
= 139.38

H maths6a
Good Morning

139.38 – 1.3938 is not equal to 136.62 (the difference between the new number and the original number was 136.62 )

A logical answer is 138

138 -1.38 gives you 136.62

Best wishes

[Tang]

tianzhu:

maths6a:

99 units --- 136.62
101 units --- 101 x 136.62 /99
= 139.38

H maths6a
Good Morning

139.38 – 1.3938 is not equal to 136.62 (the difference between the new number and the original number was 136.62 )

A logical answer is 138

138 -1.38 gives you 136.62

Best wishes

Hi,

Maths6a's answers are correct.

139.38 is the sum of the 2 numbers --- that is 101 units
and not the original number or 100 units.

[tianzhu]

Tang:

Hi,
Maths6a's answers are correct.
139.38 is the sum of the 2 numbers --- that is 101 units
and not the original number or 100 units.

Hi Tang
Good Morning

Yes, the correct answer is 139.38.

I am sorry for the mistake.

Best wishes