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more limiting sum questions!!! (2 Viewers)

atakach99

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A frog jumps 0.5m. It then jumps 0.1m and on each subsequent jump travels 0.2m of the previous distance. Find the total distance through which the frog jumps.

I need help setting this question out
can somebody plz explain how to use limiting sum formula to find answer.
thks
 

vds700

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atakach99 said:
A frog jumps 0.5m. It then jumps 0.1m and on each subsequent jump travels 0.2m of the previous distance. Find the total distance through which the frog jumps.

I need help setting this question out
can somebody plz explain how to use limiting sum formula to find answer.
thks
d = 0.5 + 0.5(1/5) + 0.5(1/5)^2 + 0.5(1/5)^3 +...
a = 0.5, r = (1/5)
limiting sum = a/(1-r)
= 0.5/(4/5) = 0.625 m
 

munchiecrunchie

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GP, a = 0.5, r = 0.2

since -1 < r < 1 , there is a limiting sum

limiting sum = a / 1 -r
= 0.5 / 0.8
= 0.625 m
 

lydia1992

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what about the 0.1 .. the question says it then jumps 0.1 m ??????????
 

qwerty44

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d = 0.5 + 0.5(1/5) + 0.5(1/5)^2 + 0.5(1/5)^3 +...
a = 0.5, r = (1/5)
limiting sum = a/(1-r)
= 0.5/(4/5) = 0.625 m
Wouldn't you have to multiply it by two because your solution only accounts for the jumping up, but not when the frog comes down after reaching its height?

So while the first jump was 0.5m high, the frog essentially jumped a total of 1m. So the final answer would be 0.625 x 2=1.25m

The total distance in which the frog travelled is 1.25m
 
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RealiseNothing

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Wouldn't you have to multiply it by two because your solution only accounts for the jumping up, but not when the frog comes down after reaching its height?

So while the first jump was 0.5m high, the frog essentially jumped a total of 1m. So the final answer would be 0.625 x 2=1.25m

The total distance in which the frog travelled is 1.25m
It's 0.625, the distance is along the ground, not in the air.
 

qwerty44

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It's 0.625, the distance is along the ground, not in the air.
Well it says, the distance through which the frog travelled. It didn't travel through 0.625m along the ground, it travelled through 1.25m of air. I no it sounds stupid but i got a similar question with a ball bouncing.

EDIT: It depends whether the question meant he jumps 0.5m high or across. OP is that the full question? Also what is the answer?
 
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RealiseNothing

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Well it says, the distance through which the frog travelled. It didn't travel through 0.625m along the ground, it travelled through 1.25m of air. I no it sounds stupid but i got a similar question with a ball bouncing.

EDIT: It depends whether the question meant he jumps 0.5m high or across. OP is that the full question? Also what is the answer?
It's across, hence it's 0.625.
 

SpiralFlex

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*Points to date of the original post*

From memory this question is from the MIF book. Yes 0.625 is the answer.
 

CM_Tutor

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@Lemon01, are you unclear on the answers provided above? Is there something that we could clarify?
 

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