Bacteria!!!!

i am not sure whether you really need the second statement.

here is my solution

statement I
2 hours ago let the population of bacteria = x
now the population = 4x (quadrupled)
or
now the population is x+3750 (population increased by 3750 in 4 hrs)

4x = x + 3750
3x = 3750
x=1250

also, population became 4 times in 2 hours

therefore, the population became double in 1 hr and then doubled again in the next hour - hence, quadrupled in 2 hours

2 hrs ago - 1250
1 hr ago - 2500
now - 5000
1 hr from now - 10,000
2 hrs from now - 20,000
3 hrs from now - 40,000
4 hrs from now - 80,000

statement I is sufficient.

statement II

now population = x
3 hours from now population = 40,000

we have no way to find the rate so Statement II is insufficient.

imo A

rohangupta83 wrote:i am not sure whether you really need the second statement.

here is my solution

statement I
2 hours ago let the population of bacteria = x
now the population = 4x (quadrupled)
or
now the population is x+3750 (population increased by 3750 in 4 hrs)

4x = x + 3750
3x = 3750
x=1250

also, population became 4 times in 2 hours

therefore, the population became double in 1 hr and then doubled again in the next hour - hence, quadrupled in 2 hours

2 hrs ago - 1250
1 hr ago - 2500
now - 5000
1 hr from now - 10,000
2 hrs from now - 20,000
3 hrs from now - 40,000
4 hrs from now - 80,000

statement I is sufficient.

statement II

now population = x
3 hours from now population = 40,000

we have no way to find the rate so Statement II is insufficient.

imo A

"If the population quadrupled during the last two hours, it doubled twice during that interval, but this does not necessarily mean that the population doubled at 60 minute intervals. It may have, for example, doubled at 50 or 55 minute intervals. We cannot determine from statement (1) how frequently the population is doubling." :twisted:

logitech wrote:
"If the population quadrupled during the last two hours, it doubled twice during that interval, but this does not necessarily mean that the population doubled at 60 minute intervals. It may have, for example, doubled at 50 or 55 minute intervals. We cannot determine from statement (1) how frequently the population is doubling." :twisted:

damn! i fell into the trap!

Rohan dont sweat too much. IMO this is a 900+ question(since it required verbal and qiuant skills)

Nice problem I agree but I would guess and move on. It better be an experimental one

iamcste wrote:can feel bacteria around...


In such cases, I either choose C or E

so, I still have a 50-50 chance

I think the choice is between A and C

Oh well, if you see a problem like this in your test. Smile and remember me!