Tutor MathsGuru: Ask me for your burning Maths questions!

[Hifive]

Hi, need help with this question:


If @@### = 68, find the value of @@@#####.

Thanks in advance!

[small]

Hifive:

Hi, need help with this question:


If @@### = 68, find the value of @@@#####.

Thanks in advance!

I think something is missing there. :oops:

[Hifive]

Hi small


Thanks for your reply. This is a question from my son’s school homework. I’ve tried for quite a while but can’t get any solution. Pls help.

Thanks

[worldangel]

small:

worldangel:

I have a question here:


If the question never states to leave the answer as fraction/mixed number or decimal, can the child leave the answer as a decimal and still get it correct?

For example, the child writes the answer as 6.66667 = 6.67. The answer is
6 2/3.

This is for a question in Paper 2 btw. Thanks in advance

Hi worldangle,

My opinion is 6 2/3 will be good enough and sufficient and yet the kid not need to spend more time.

Yea but Paper 2 they can use calculator so they decided to leave their answer in decimal....I dunno what's going on in their head...and it was marked wrong...

[worldangel]

CoffeeCat:

worldangel:

I have a question here:


If the question never states to leave the answer as fraction/mixed number or decimal, can the child leave the answer as a decimal and still get it correct?

For example, the child writes the answer as 6.66667 = 6.67. The answer is
6 2/3.

This is for a question in Paper 2 btw. Thanks in advance

Even if you chose to leave as a decimal, should write 6.67 (correct to 2dp).

Yup, the answer was left as 6.67....but it was marked wrong....

[CoffeeCat]

Yea I mean 6.67 by itself is asking to be marked wrong.

Hifive:

Hi, need help with this question:

If @@### = 68, find the value of @@@#####.

Thanks in advance!

This question by itself is indeed diabolical. Maybe you wana elaborate on what level this is?

[YLH88]

Hi Mathsguru,


Need your help with the following questions : :?:

1) At first, there were 230 kg of oranges and durians in a market. After 60% of the oranges and 20 kg of the durians were sold, the remaining oranges and durians were of equal weight. What was the original weight of the durians ?

2) There are 480 people in Group X and 20% of them are children. There were 380 people in Group Y and 70% of them are children. After some people were transferred from Group Y to X, 40% of the people in Group X and 50% of the people in Group Y are children. How many people are transferred from Group Y to Group X ?

3) Mrs Winder had some $50 notes and $10 notes. The number of $50 notes is 45% that of $10 notes. She spent 20% of the $50 notes. As a result, she had 192 more $10 notes than $50 notes.
(a) What was the amount of money spent ?
(b) Express the amount of $10 notes as a fraction of the amount of $50 notes left.


Thank you very help !

[worldangel]

CoffeeCat:

Yea I mean 6.67 by itself is asking to be marked wrong.

Hmm...care to elaborate what you mean? She did all the working but instead of writing the final answer as Ans: 6 2/3, she wrote it as Ans: 6.67...


Of course before that final answer, all the working and steps were shown clearly. Just that instead of using mixed number, she used decimal...so the final answer was left as a decimal. So she lost the one mark for the answer because the teacher claimed it should be left as mixed number, not decimal. But that was not stated in the question...that's why we were wondering why the final answer in decimal is not accepted.

Thanks in advance again.

[CoffeeCat]

worldangel:

Hmm...care to elaborate what you mean? She did all the working but instead of writing the final answer as Ans: 6 2/3, she wrote it as Ans: 6.67...



Of course before that final answer, all the working and steps were shown clearly. Just that instead of using mixed number, she used decimal...so the final answer was left as a decimal. So she lost the one mark for the answer because the teacher claimed it should be left as mixed number, not decimal. But that was not stated in the question...that's why we were wondering why the final answer in decimal is not accepted.

Thanks in advance again.

oh ok you see, 6.67 is not the same quantity as 6.66666...
That is why if you write 6.67 (correct to 2 d.p), then there is a fighting chance to get the marks.

[CoffeeCat]

YLH88:

Hi Mathsguru,


Need your help with the following questions : :?:

1) At first, there were 230 kg of oranges and durians in a market. After 60% of the oranges and 20 kg of the durians were sold, the remaining oranges and durians were of equal weight. What was the original weight of the durians ?

2) There are 480 people in Group X and 20% of them are children. There were 380 people in Group Y and 70% of them are children. After some people were transferred from Group Y to X, 40% of the people in Group X and 50% of the people in Group Y are children. How many people are transferred from Group Y to Group X ?


3) Mrs Winder had some $50 notes and $10 notes. The number of $50 notes is 45% that of $10 notes. She spent 20% of the $50 notes. As a result, she had 192 more $10 notes than $50 notes.
(a) What was the amount of money spent ?
(b) Express the amount of $10 notes as a fraction of the amount of $50 notes left.


Thank you very help !

I am not mathsguru but...
1)Weight of 60% of oranges + 40% oranges + 40%oranges = 230-20=210.
Weight of 40% oranges = 210 * 40 % / 140% = 60kg
weight of durians = 60 + 20 = 80kg

What level is this from anyway?

2)Number of children in X = 20% * 480 = 96
Number of adults in X = 384
Number of children in Y = 70% * 380 = 266
Number of adults in Y = 114

After the transfer...
40% of X + 50% Y = 96 + 266 = 362 children
60 % of X + 50% of Y = 384 + 114 = 498 adults
20% of X = 498 - 362 = 136
X = 136 * 5= 680
Number of ppl transfered = 680 - 480 = 200
(Key is that the total number of children and adults is constant)

3)
a)Number of $50 notes is 45% of $10 notes
After spending 20% of the $50 notes, the number of $50 notes left is (80% * 45%) = 36% of $10 notes
192 = (100-36= 64)% of $10 notes
Amount of money spent = (192/ 64%) * (45%-36%) = $27

b) Ans = reciprocal of 36% = 100/36 = 25/9

My workings might not be very clear. The real Mathsguru will probably give you a better form.