Question

Plz help...I'll be ur fan................

Blake goes running for 10 minutes on Sunday. Every day he doubles his running time. If he continues this pattern, how many minutes will he run on the 7th day?

I'm confused about which formula I should use:
f(n) = f(1) • r^(n−1) or an = a1 • r^(n−1)
are these even the correct formulas for this question????

Answer 1

@moazzam07

Answer 2

yes those are the correct ones and both say the same thing
if you use the second one, a1=10, r=2 and n=7

Answer 3

So that means that on the 7 day he would run 640 minutes???? @rajat97

Answer 4

i'm calculating!

Answer 5

yes you are right

Answer 6

what do you mean by doubling

Answer 7

no that's not right @princeharryyy has got it

Answer 8

day 1 =10 =10
day2 = 2*10 =20
day3 = 2*2*10 =40 .....
day7 = (2^6 )* 10 = 64*10 =640minutes @rajat97 and @plzzhelpme

Answer 9

and that was right @rajat97

Answer 10

wait........it was right..

Answer 11

oh yeah! silly me!

Answer 12

yeah! silly you! that was right.

Answer 13

ok thanks alot...
what formula would u use for this question??

Alex studies for an exam for 50 minutes on Monday. Every day he increases his study time for 5 minutes. If he continues this pattern, how many minutes will he study on the 7th day?

Answer 14

this is an arithematic progression

Answer 15

you can use a1 + (n-1)d

Answer 16

here d=5, n=7and a1=50

Answer 17

50, 50+5, 50+5+5, 50+5+5+5, ..... and so on

Answer 18

and that would be 80 minutes on day 7 right?

Answer 19

yup

Answer 20

ok....thanks alot:* :* :*

Answer 21

* :* :*