Tutor MathsGuru: Ask me for your burning Maths questions!

[CJM]

Yu Xuan:

CJM:

Some trees are planted along a 400 metres road with a tree on each end of the road. The distance between every 2 nearest trees are 4 metres. If the distance between every 2 nearest trees is to be changed to 5 metres, how many trees will not be removed?

400 / 4 = 100
100 + 1 = 101

400 / 5 = 80
80 + 1 = 81

101 - 81 = 20

Is that the answer?

the teacher has not posted the answer yet : )
thanks for ur help !

[maths6a]

i also calculated 20. all the trees that were planted on mulitples of 5 and 10, in this case are the ones on 20m, 40m,… and 20 tress need not be removed.

[CJM]

maths6a:

i also calculated 20. all the trees that were planted on mulitples of 5 and 10, in this case are the ones on 20m, 40m,... and 20 tress did not be removed.

thank u : )

[Yu Xuan]

I think I cause some confusion, my first working is wrong... I realised it after reading it again. I have edited my answer and hence my answer is 21 instead after adding the first tree.


Sori abt that :lol:

[Tang]

Yu Xuan:

CJM:

Some trees are planted along a 400 metres road with a tree on each end of the road. The distance between every 2 nearest trees are 4 metres. If the distance between every 2 nearest trees is to be changed to 5 metres, how many trees will not be removed?

Multiple of 4 that has a '0' in the ones place are... It is multiple of both 4 and 5, ie 20.

20, 40, 60, 80, 100, 120, ... (20 in total)

20+1 = 21

Is that the answer?

Hi,

4 x 5 = 20

400 / 20 = 20

20 + 1 = 21 trees will not be removed.

[Tang]

CJM:

maths6a:

i also calculated 20. all the trees that were planted on mulitples of 5 and 10, in this case are the ones on 20m, 40m,... and 20 tress did not be removed.

thank u : )

Hi,

Don't forget to add the one at '0'.

[Cheerfuldad]

Hi all,


Please help!

Q. Beth had 40% more beads than Diana. After Beth gave 10% of her beads to Diana, She had 48 more beads than Diana.

a) How many beads did the two girls have altogether?

b) How many beads must Beth give to Diana so that both girls would have the same number of beads?

TIA.

[Daddy]

Thanks Tianzhu & Dharma.


Tianzhu Question:
"Mr Ong had 5kg of rice. After he sold 5/12 of it, he repacked the remaining rice into smaller packets of 2/3kg each. How much rice had he left? "

Above question is difficult than I had asked. I tried.

Left => 1- 5/12 = 7/12

5 Kg x 7/12 = 35/12kg left

Is it the answer?

[maths6a]

you are right. so plus first tree so it should also be 21. pai say!

[tianzhu]

Daddy:

Thanks Tianzhu & Dharma.


Tianzhu Question:
\"Mr Ong had 5kg of rice. After he sold 5/12 of it, he repacked the remaining rice into smaller packets of 2/3kg each. How much rice had he left? \"

Above question is difficult than I had asked. I tried.

Left => 1- 5/12 = 7/12

5 Kg x 7/12 = 35/12kg left

Is it the answer?

Hi

You're welcome.

5 Kg x 7/12 = 35/12kg left
You’ve answered the first part of the question.
From the remainder of 35/12kg, you have to take into account the repacking of the remaining rice into smaller packets of 2/3kg each to get the answer.

Like your earlier question, this one also touches on product of proper fractions. Such questions may look easy at first glance, but may trip some students as they can be tricky.

The answer is 1/4kg.

Best wishes