Please help on this question

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ReplayMum
Posts: 117
Joined: Tue May 10, 2011 2:12 pm

Please help on this question

Post by ReplayMum »

Could someone please help on this question?

Ladybirds eat greenfly.
On one bush, there are enough greenfly to feed 9 ladybirds for 4 hours.

a) How long would the greenfly last if there were only 6 ladybirds?

b) How many bushes would be needed to feed 36 ladybirds for 2 hours
aargh
Posts: 406
Joined: Mon Oct 10, 2011 7:00 pm

Re: Please help on this question

Post by aargh »

just edited to delete my DS confusing post
Last edited by aargh on Tue Jan 03, 2012 6:24 pm, edited 1 time in total.
svg123
Posts: 250
Joined: Thu Feb 24, 2011 1:34 pm

Re: Please help on this question

Post by svg123 »

Won't it be 2 bushes for the second question.
1 bush = 9 lady birds for 4 hours = 18 lady birds for 2hours
Therefore, 2 bushes can feed 36 lady birds for 2hours.
aargh
Posts: 406
Joined: Mon Oct 10, 2011 7:00 pm

Re: Please help on this question

Post by aargh »

Well yes it will svg123
That rather confusing post above seems to have been posted by DS :roll: and he missed off his reason for the first answer.
I have had words with him about going on my forums :!: How do I delete it?
BarnetDad
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Joined: Thu Apr 24, 2008 10:51 pm

Re: Please help on this question

Post by BarnetDad »

Don't think you can delete a post completely. Editing it as you have done is best.
dadofthree
Posts: 2
Joined: Mon Oct 31, 2011 6:13 pm

Re: Please help on this question

Post by dadofthree »

a) One bush allows 9 ladybirds to eat for 4 hours.
That's 36 "eating hours" in total.
If there were only 6 ladybirds, then the 36 hours would last them 6 hours.

b) One bush lets 9 feed for 4 hours. Again, allowing 36 "eating hours"
This 36 hours from one bush should allow 18 to feed for 2 hours.
We need enough bushes for 36 ladybirds for 2 hours - so two bushes should be enough.

That's how I've worked it out - apologies if wrong!

=
ORIGINAL QUESTION BELOW
Ladybirds eat greenfly.
On one bush, there are enough greenfly to feed 9 ladybirds for 4 hours.
a) How long would the greenfly last if there were only 6 ladybirds?
b) How many bushes would be needed to feed 36 ladybirds for 2 hours
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