#8th class question please help

45 messages · Page 1 of 1 (latest)

clever barn
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can anyone answer?

devout rune
# clever barn

The time to dig a hole must be inversely propotional to the number of people.

clever barn
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so it would be 3

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3 days?

devout rune
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No.

clever barn
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so?

devout rune
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Well, I should be asking you.

clever barn
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so it could be 4?

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cause only 2 ppl gained

devout rune
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Well, did you calculate it or did you just guess?

clever barn
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No i guessed it

devout rune
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That doesn't count.

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Suppose the number of people digging a hole is n and the time needed to dig it is t. Then:
nt = const
So, for two pairs of values of (n, t) we get:
n1t1 = n2t2
We know n1, t1 and n2. So:
t2 = (n1/n2)t1
Substitute n1 = 8, n2 = 10, t1 = 5 days to get the answer.

clever barn
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5days?

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is it 5 days?

devout rune
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Well, it can't be 5 days again...

clever barn
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It could be 4.5 days?

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I mean 4 days 12 hours?

devout rune
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Uh...

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We literally got the formula already, why are you guessing...

clever barn
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well,

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Ig i cant understand

devout rune
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We have t2 = (n1/n2)t1.
Substitute n1 = 8, n2 = 10, t1 = 5 days to get the answer.

clever barn
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then what is it?

devout rune
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Just substitute the numbers...

clever barn
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i cant get u

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10-5?

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8-5-10?

devout rune
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Um, what are you doing?

clever barn
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i am trying to find

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it

devout rune
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You just need to substitute the values.
t2 = (n1/n2)t1 = (8/10)*5 days = 4 days

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That's it...

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Don't really know what you were doing. Seemed like something random, which is not useful.

clever barn
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bro

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I cant get the substitute

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Any other word for it?

forest swan
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4 days

devout rune
forest swan
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8 people 5 days
1 person 5•8=40 days
10 people is 40:10=4 days

clever barn
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well,

clever barn
forest swan
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When

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I just joined the chat