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20! 1.25 goats per day. (no bingo)

I showed this to my math teacher and asked if she could figure it out and she asked me what the hell I've been smoking.

Ian The Magic-Ian wrote:20! 1.25 goats per day. (no bingo)

.... errmm ..... nope .

If it takes 48 goats 90 days to clear the field and 120 goats take 30 days , then the required number of goats to clear the field in 16 days is gonna be more than 120 yeah ??

The problem with number riddles is you never know whether the answer is actually maths or logic. I suppose I could bring calculus into this...

moonbeam wrote:

Ian The Magic-Ian wrote:20! 1.25 goats per day. (no bingo)

.... errmm ..... nope .

If it takes 48 goats 90 days to clear the field and 120 goats take 30 days , then the required number of goats to clear the field in 16 days is gonna be more than 120 yeah ??

I was joking...I have no idea lol...

somewhere between 230 and 240?

flaw07 wrote:somewhere between 230 and 240?

.....close (ish) ........ .

Here's a hint:

.......... the main problem with solving this riddle is the fact that the grass is continually growing.

If you assume that 1 goat eats 1 unit of grass per day, then 120 goats will eat 120 units in one day and 120 goats will eat 3600 units in 30 days.
Do the same for the 48 goats and 90 days.
The difference between these two figures is the amount that the grass has grown in 60 days (90 days - 30 days = 60 days).
You can now work out how much the grass grows per day (divide by 60) and how many units of grass there are to start off with ............

Any takers ???

GYAAAGH! I'll say it again. You and your damn complex math riddles!

totally lost me

i think i got it
1 goat = 1 unit of grass per day
120 goats =120 units of grass per day
120 *30 days =3600 units of grass in 30 days
48 goats = 48 units of grass per day
48 * 90 = 4320 units of grass in 90 days
4320-3600 = 720 units of grass in 60 days
720/60=12 units of grass to start

12 units of grass X 16 days = 192 Goats

damn that was a a lot of work

moonbeam wrote:Any takers ???

215 goats (or 214 goats and a kid).

EDIT: Flaw07, you're nearly there. The growth rate has nothing to do with the starting amount.

Unless I've got it wrong, of course.

Part-Timer wrote:

moonbeam wrote:Any takers ???

215 goats (or 214 goats and a kid).

EDIT: Flaw07, you're nearly there. The growth rate has nothing to do with the starting amount.

Unless I've got it wrong, of course.

You are correct.

You were close flaw07 .....

You were correct up to:

flaw07 wrote:4320-3600 = 720 units of grass in 60 days

....... this means that the grass grows at 12 units per day. i.e. 12 goats will eat exactly what grows.
The amount of grass at the start must = total amount eaten - the new growth ....... so in the 30 day case:
Amount at start = 3600 - (30 x 12) = 3240 units.
This should also be the same for the 90 day case, so just to check:
Amount at start = 4320 - (90 x 12) - 3240 units.

In 16 days 3240 units would be eaten by 3240 / 16 = 202.5 goats
12 goats are needed to eat to eat up any new growth, therefore to clear the field in 16 days would require 214.5 goats ..... rounded up to 215 goats.

Terry and Teri are twins (and yes, twins with each other, to the same parents, born in the same year). Terry is older than Teri, but sometimes he celebrates his birthday two days after her.

Why?

One was born before midnight Feb 28th, and one after midnight feb 29th?