Data Sufficiency

$10,000 is deposited in a certain account that pays r percent annual interest compounded annually, the amount D(t), in dollars, that the deposit will grow to in t years in given by D(t)=10,000(1+(r/100))t What amount will the deposit grow to in 3 years?

(1) D(t) = 11,000
(2) r=10



IMO B. OA D

IMO, it's B.

We're given the standard compound interest formula, and we're asked what the $10,000 deposit will grow to in 3 years.

1) Not sufficient. While we're given the future value of the deposit, we don't know the rate (r), and we don't know the number of years (t).

2) Sufficient. You can fill in the formula since we're given the rate (r) and time (t).

A will be SUFF if we are told that
D(t) = 11,000 is a total amount from 1 year deposit

4meonly wrote:A will be SUFF if we are told that
D(t) = 11,000 is a total amount from 1 year deposit

Stem A only says 11,000. It never indicated how long it took the money to grow. Therefore, A is not sufficient.

I think either of 2 statements is sufficient!

the equation is D(t)=10,000(1+(r/100))t. T is already given as 3. So the only variables are D(t) and r.

from St1, D(t) is given and solve to get r and the equation is complete. so sufficient.

From St2 r is given and solve to get D(t). and hence sufficient too!

What you say?

Azntycoon wrote:

4meonly wrote:A will be SUFF if we are told that
D(t) = 11,000 is a total amount from 1 year deposit

Stem A only says 11,000. It never indicated how long it took the money to grow. Therefore, A is not sufficient.

Agree, that is exactly what I said

Are you sure there isn't a typo? Is statement (1) supposed to say:

D(1) = 11000?

If we know that D(1) = 11000, we can solve for r, which means we can answer the question.

D(1) = 11000 is also consistent with the information given in statement (2) (i.e. if we solve for D(1) = 11000 we get the value r=10), which further increases my certainty that statement (1) has been misquoted somewhere.

As an aside, saying that D(t) = 11000 doesn't make sense, but it is sufficient to answer the question. If D(t) is constant, then any value you plug in for t will give you the same answer, 11000.

So, technically speaking, statement (1) is sufficient as written, but it makes no sense.

What's the source of this question?

I am sure it must be a typo
but
whatever it may be.....

the answer can never be A
it is D


A
D(t) = 11000
you have your answer
whatever t may be, the ans is 3
sufficient


B
r=10
solve it, u have r and t
sufficient

so ans is D


correction:
I think d(t) must be d(1)
10K at 10% after 1 year will become 11k

so even if its d(1)
the answer will still be D
because we can find r from d(1)