Question

A savings account starts out with $0.50 and doubles every month. Write an equation that models this situation and determine how much money will be in the account in 2 years

Answer 1

its easy

Answer 2

you have to multiply .50x2x24

Answer 3

Because it doubles

Answer 4

but like .50x2

Answer 5

then x24

Answer 6

then 1.00x2

Answer 7

which is one...

Answer 8

2....

Answer 9

yup

Answer 10

and you have to do that procees 24 times

Answer 11

i messed up dont do x24

Answer 12

Well, that's wrong, because it is an exponential growth problem and i need an equation...

Answer 13

I mean it's right, but it's not what I need

Answer 14

just do the procces 24 times to dertermine the snaswer

Answer 15

Yes, but I need an equation too.

Answer 16

ok

Answer 17

hey

Answer 18

Helpppp

Answer 19

y = 0.5*2^x , where x = number of months

Answer 20

I would go with Y=X exponent 2 x2

Answer 21

imma go to english

Answer 22

x is supposed to be number of years.

Answer 23

it is f(x)=(2^x)/2 like perl said

Answer 24

y = 0.5 * 2^(12*x)

Answer 25

because it doubles 12 times in a year

Answer 26

Yes, but wouldn't it be .5(25)^t?

Answer 27

no the amount double each month
with the initial value f(0)=0.5

Answer 28

Listen, this is an exponential growth problem. SO, the equation for it would be A(1 +r)^t
A= 0.5, r = 24, and t = # of years (2)

Answer 29

therefore, it should be 0.5(1+24)^2

Answer 30

this one y=0.5*2^(12x) is an exponential growth as well

Answer 31

this is confusing....

Answer 32

where did you get r=24? r repesents the rate my dear

Answer 33

in fact you can't say A(1+r)^t this interest formula you know
you need to find the interest rate r and the number of compounding

Answer 34

usually as we compound continuously we get the number e^r not 25 like you did

Answer 35

it's asking for the amount after 2 years. The amount DOUBLES each MONTH 2 x 12(month) = 24

Answer 36

r is not 24

Answer 37

why are you making your life harder, while the problem didn't ask you anything about interest ?

Answer 38

If something doubles that means
r = 100% ,
or in decimal
r = 100/100 = 1

Answer 39

yes @perl has given you the formula for getting that
\(y=0.5*(2)^{12x}\)

Answer 40

Listen, its not asking about intrest, it's asking about what the amount will be in 2 years aka 24 months

Answer 41

I know! you are the one who is thinking about a different approach to the problem

Answer 42

y = A ( 1 + r)^t

here A = 0.5
r = 1
t = variable in months

y = 0.5 ( 1 + 1) ^t

and then you said t is in years , so i changed it

y = 0.5 ( 1 + 1) ^(12t)

Answer 43

Because this is the approach I am being taught

Answer 44

r is the rate it increases per time period. it increases by 100% or by a factor of 1

Answer 45

hmm, I agree with perl

Answer 46

you guys are probably right, I'm just asking if the equation, .5(25)^t is right

Answer 47

no, it isn't

Answer 48

for the reasons given above :)

Answer 49

...

Answer 50

Then what would r be?

Answer 51

r equals 1

Answer 52

Wait, just tell me the total answer for the problem.

Answer 53

Is the total $312.50?