Question

A ball is dropped from a height of 10m. It bounces to a height of 6m, then 3.6m, and so on following a geometric sequence. Find the total distance travelled by the ball.

Hint: Use of sum to infinity and sum to certain term of a geometric sequence.

Answer 1

who are you.

Answer 2

first term = 10
common ratio = 0.6
now plug in the values in the formula

Answer 3

sus*

Answer 4

tell me the answer

Answer 5

i know the first term is 10 and common ratio is 0.6 lol...

Answer 6

my answer does not match with the answers at the back of the textbook

Answer 7

what is the formula that you are using???

Answer 8

Sum to infinity = a/(1-r)

Answer 9

a being first term, r being common ratio

Answer 10

Sum of geo series = a(1-r^n)/(1-r)

Answer 11

a=10 (or not) r=0.6

Answer 12

i got 25m, but the answers say 40m, proof pl0x

Answer 13

thanks for viewing guys - need answers, any will do

Answer 14

as long as it's correct

Answer 15

Every term after the 10 is twice (down and up)...

Answer 16

yes

Answer 17

For 25 you counted once or twice?

Answer 18

once, it's wrong

Answer 19

so i guess it's something like 10+ ...sum from term 2 to infinity?

Answer 20

i'll try it

Answer 21

10 + twice * sum I think...

Answer 22

a(1-r^n)/(1-r) = sum of geometric sequence to n
a/(1-r) = sum to infinity
2x sum to infinity - first term!!!!!!! woot got it
25x2 - 10

Answer 23

thanks :]

Answer 24

i'll give you a medal for attempting

Answer 25

tricky bastard questions... lol

Answer 26

U r welcome.

Answer 27

I will give u a medal for doing it, lol

Answer 28

Hmm... I can see there are 2..sum of inf.
1. first term =10, r=0.6
Sum = 10/(1-0.6) = 25
2. first term = 6, r=0.6
Sum = 6/(1-0.6) = 15
So.. Total sum = 25+15=40

Answer 29

wow, i didn't see that

Answer 30

The first one is the one it drops...
The 2nd one is the one it goes up.
Total distance = total drops + total rise

Answer 31

e^i pi ftw

Answer 32

ahah!

Answer 33

damn you're good

Answer 34

Do you get it now?

Answer 35

yes, tyvm

Answer 36

You're welcome :)

Answer 37

can you explain e^ipi plox?