#i have tried but cannot get the answer

111 messages · Page 1 of 1 (latest)

chilly nimbus
sand pagodaBOT
astral spear
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23 and 24 are geometric series questions

Sn = a+ ar+ar^2+ar^3+...+ar^n
Sn = a(1-r^n)/(1-r)

25 is exponential growth
y=Cexp(rT)

chilly nimbus
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I got 25th but 23 and 24 i am not getting

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,rotate

placid currentBOT
chilly nimbus
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23 i have found the total

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But there is one more thing which i have to find

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That part
"The farmer calculating quickly........ten dollars"
Hires the tramp for 6 months
Did he make a wise bargain

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Now what does the question mean by did he make a wise bargain?

dull sphinx
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For 23) I says he hired him for 6 months (=24 weeks), but then talks about the entire period being 26 weeks.... either way, yeah it's a bum deal for the employer. He should have studied math more lol

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dull sphinx
chilly nimbus
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Thats for sure unless he plants those greens

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And ya one part says i have to find the 26th weeks wages

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Can you help with 24 ?

astral spear
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use the geometric sum relations I gave you

chilly nimbus
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I have used

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I got 3 different ans 3 diffnt times

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Once i got close to the ans

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The relation is even in my knowledge

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If the ball bounces i have to double the distance it travels in each bounce like in 1st 40 ft so 80 ft once up and downand also it says after leaving the handso i have to consider that distance too which i can approximate as 40 ft
Right?

astral spear
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a = 40; r = 16/40 = 0.4; n = 5

Sn = a(1-r^n)/(1-r) = 40(1-0.4^5)/(1-0.4)

chilly nimbus
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a = 80?

dull sphinx
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Yeah for 24:

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chilly nimbus
dull sphinx
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25: there should be a 256x increase in the original bacteria amount after 24 hrs?

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chilly nimbus
# dull sphinx Yeah for 24:

I believe we do not have to add the 0.82 bcoz at 5th time it hits the ground and goes up and again comes down travels a distance 2.05 and after that distance it has hit the ground for 6th time and we need the ans for when it strikes the ground for 6th time then we'll get
Total = 131.97

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And also from the time it leaves the hand so i have to consider that distance too which can be approximated as 40

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Giving total as 171.97

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?

dull sphinx
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Hitting the ground for the 6th time is the end of the set... the 6th up and down. It's thrown up first, so the first hit on ground is 1, the 2nd, 2.... 6 is 6th

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So you need to include the distance up and down for the 6th set, not just down

chilly nimbus
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Perhaps the answer key is wrong

chilly nimbus
dull sphinx
chilly nimbus
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Well that is all about the distance it covered when the ball was bouncing around and it asks total distance travelled after leaving the hand

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Well its not mentioned here how much distance it travelled when thrown upwards so

dull sphinx
chilly nimbus
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Ya

dull sphinx
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Oh that's a good point.... there's another bounce before the 40 ft one... hold one

chilly nimbus
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Ya

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If it was just released

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We could have approximated the distance as 40 ft

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But since its thrown we can't tell

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buds thanks for the help

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Well there's one more if you wouldn't mind?

dull sphinx
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Try this,

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You can tell.. it's the same 2.5 ratio applied to the initial toss

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I enjoy a good trick question, good catch

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So it's first thrown up 100 feet... comes back down then bounces 40ft etc...

chilly nimbus
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Ya

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Hat makes sense

dull sphinx
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But you're right, it traveled 200 ft before the first bounce, which should be included in the sum

chilly nimbus
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But ans given is 165.984 ft

dull sphinx
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"after leaving the hand"

chilly nimbus
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It can be wrong perhaps

dull sphinx
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Lol I'd say the answer key was wrong... who ever wrote it probably wasn't thinking about the inital toss in how it was worded lol

chilly nimbus
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Dk it is a pretty old book

dull sphinx
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Odd that 165.984 f is almost 1/2 the answer I gave 332.79

chilly nimbus
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Yes i too was wondering the same

dull sphinx
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"Total distance traveled after leaving the hand..." means to include the up/down of the inital toss (100ft+100ft) as this is 2.5 more than the first 40ft bounce

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Extra credit to you!

chilly nimbus
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Do you think that 40 ft includes the up and down both ?

dull sphinx
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By the way, it's absurd... no body can "toss" a ball 100ft in the air anyways lol

chilly nimbus
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Well let me tell you something ironical the book is named "arithmetic for the practical man"

dull sphinx
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No because it says it "bounces" 40 ft the first time (meaning up then down)

dull sphinx
chilly nimbus
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lol

chilly nimbus
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But if we consider it is both up and down

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Then

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We get 166.3936

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Well theres one more lets keep that for tomorrow

dull sphinx
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Whaddya mean ... we get 166.39?

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What was your other question?

chilly nimbus
chilly nimbus
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Then we'll get the sum as 166.39 ft

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Which is pretty close to the answer assigned

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Here

dull sphinx
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Wow I cannot get it to sum to 166.39

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Think it's the wording... it literately states the ball is thrown up, it travels down, hits the ground, then bounces up to 40 ft, and back down again

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So literally that's the inital toss 100 ft up + 100 ft down, then 1st ground bounce, then 40 ft up, then 40 down, then 2nd ground hit, and so forth...

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What that does do is make the 1st ground hit the one after the initial toss... so my prior 6th bounce was wrong (also, the thrower's hand when tossing is not at ground level either, so technically there's about 4 ft to subtract off as well that I didn't do):

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26 is a classic pyramid mail scam lol ... seen this before

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For 26, the "charity" is going to get audited by the IRS:

chilly nimbus
chilly nimbus
dull sphinx
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I totally divided wrong in that 26 per person payment question.... should be about $659.00 per person (If it's net remit- stamp total / 135M) or $941.43 (Remit/135M)

chilly nimbus
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Bro where u from?

deft belfry
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lol

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@chilly nimbus are you given an answer forthese questions

chilly nimbus
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23 we have found Correctly

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  1. 26th week, $335,544.32
    Total, $671,088.63

  2. 165.984 ft

  3. 128 times as many as at start

  5. $32,391,432,811.14
    2)$ 9,717,429,811.14

  6. About 2400

placid currentBOT
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pumpkineater96

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chilly nimbus
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@deft belfry

deft belfry
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is this the answer key or are these the answers you have so far

dull sphinx
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I'm very curious how you both are getting 24) 165.9 ft... can you show how you arrived at that?

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  1. 128x in 24 hrs? How? There's 8 doubling periods, 2^8 = 256... it's doubles 256 times in 24 hrs if it doubles every 3 hrs
dull sphinx
chilly nimbus
chilly nimbus
chilly nimbus
dull sphinx
chilly nimbus
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Even i am getting 256 according to the words

dull sphinx
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    1. They have $32B? .... you can easily sum those up on the spreadsheet and get $127B ... don't think I messed up that pyramid that bad
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Revised:

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