math

Chefboyardeeezie,

I believe this is a problem of probability, which means we have to multiply fractions. We want to get the fractions of every group who might lend him money. So the first group has 2/3 (remember this is about who WILL lend him money, not who WON'T. If 1/3 won't lend, 2/3 will.), the second group has 2/5, and the last group has 1/2. So, writing this out as an equation we get:

(2/3)*(2/5)*(1/2) = 4/30, but we have to simplify down to 2/15.

So, if he asked 60 people, and 2/15 lent him money, some quick math and logic (let me know if you need me to write this last part as an equation, too!) tells us that 8 people out of the 60 lent him money.

Hope that helps!

Warm Regards,
Grammar Fascist

Love your explanations Grammar Fascist.
Side note to Grammar Facist just wondering if multiplication was correct use in the equation you did, as you discarded someone, you imply say's yes. Shouldn't it have been addition?

unicorns are yo mama

abc:

unicorns are yo mama

Don't derail the thread with such poppycock and swiddleswosh

Stu,

He's not asking the same group three different times. Instead, he's asking the same group and it progressively gets smaller as more and more people turn him down. Of the original 60, 1/3 WON'T help him, so 2/3 WILL maybe help him. Of the 2/3 of the original 60 who might help him, 2/5 of that group quickly inform (and I assume that's inform and binform is incorrect.) him that they might help. Of the 2/5 of the 2/3 of the original 60 people, 1/2 WON'T help him, thus, 1/2 WILL help him. So, you end up with: 1/2 of 2/5 of 2/3 of 60--equation form: (1/2)(2/5)(2/3)(60) = number of people who will help. Yes, it is multiplication. Simply because you're narrowing down the same group, not asking the same group three different times. I can't really explain it much better than that. I don't know the exact science (err, math, I guess) behind it, but I know that it's a probability problem and that you multiply fractions in those. Perhaps Rom or Melody could shed some light on the semantics of why you multiply.

Thanks for the high praise, man! That's kind of you; I just like helping people! However, I'm afraid my experience is severely limited compared to some other users here. When it comes to projectiles and LaTex, I'm completely lost. I'll love those to the pros! ;D

Warm Regards,
Grammar Fascist

But .. 1/2 of the remainder- this should be applied to all that were called from the 60 who did not give an answer on other grounds then. It's the only other logic when reading the wording of the question. Either that or each event is related to the group he asked which is 5.And he didn't have to ask the group 3 times, to get 3 sets of results from one group. The wording definately seems to go infavour of him only having asked one group, and we are calculating for that group, given 3 types of answers from the different members. That group being either 5, or being 60 with 4 answers and 56, where 2 of every 5 now left say no and the remaining has half do not give a loan. This still doesnt provide us with the answers of the 1/2 that have not denied to loan money as that doesn't mean they said yes. That could have said maybe.

Looking at your answer this would be true, or something like it..


60/3 = 20 who deny of the top. FRom the 40 left, 2 in 5 say no = (40/5)*2 = 16 who say no. total so far 36 who say no, and 1 in 2 left who say no is remaining 24/2 = 12 who say maybe yes maybe no, yes or no..
According to this our best guess on what we now have its a guesstimate at 50% to say yes, either directly or maybe yes given what we know. But it's only a guestimate.. and it is also in fact 12 who say no and 12 who say yes. so the answer in my opinion is:yes is equal to between 0 and 12

^i can see how wording is able to read like this. But this answer above would seem right according to the wording order and what you've said's happening as he places calls..

Chefboyardeeezie:

Bob is trying to borrow $1,000 from a group of friends. One of every three friends asked responds that their money is already tied up in other investments. Of his friends with money not tied up in investments, 2 out of 5 inform him quickly that they will? lend him money for any reason. Of the remainder, 1 out of 2 won't lend him money just based on general principles. If Bob called 60 friends, how many lend him money?

*
Now, lets work backwards.
60 friends
1/3 cannot, 1/3 of 60 = 20
So that leaves 40 friends that might.
2/5 of of the 40 will lend him money. 2/5 * 40 = 16 Will
That leaves 40-16 = 24 friends not counted yet.
1/2 won't lend him any on principal 1/2 of 24=12
That leaves 12 that might. They have not said yet.
so
16 will lend him money and 12 might lend him money.

this place is soooo much fun!

There you go.

I was on the right track Melody. Pat on the back for me. I don't know that it says will yet though. just going on what was written.

But i agree with you, that looks just like the answer I had to the same question in high school 14 years ago.

Ah, I see. I read it wrong all together. My apologies, Chef. Go with what Melody said. ^-^ I have no degree in mathematics. Matter of fact, I'm not even out of high school. Haha, bear with me, you all.

your answer was pretty good GF. Your reasoning calling it a probability problem wasn't incorrect.

Rom:

your answer was pretty good GF. Your reasoning calling it a probability problem wasn't incorrect.

Hello Stu and Grammar Fascist,
Rom is correct.
I came at the question through the back door, but, if you came at the question from the front door, some of the logic was quite similar to probability.
You had some good ideas too Stu.
I really like that you both had a go at the question. On reflection i think that i was a little rude. Please accept my apology.
Melody.