If a light bulb is selected at random from a shipment, what is the pro

Question

Competition Mode Question

If a light bulb is selected at random from a shipment, what is the probability that the light bulb is defective?

(1) The ratio of the number of defective light bulbs to the number of nondefective light bulbs is 1 to 60.

(2) The shipment contains 720 light bulbs.

freedom128 · Answer

Q. the probability that the light bulb is defective?

(1) no of defective/ no of good = 1/ 60.
--> the probability that the light bulb is defective = 1/(1+60) = 1/61
SUFFICIENT

(2) The shipment contains 720 light bulbs.
--> Since we have no information about no of defective/non-defective bulbs in a shipment, we cannot deduce the probability that the light bulb is defective if a bulb is selected from 720 bulbs at random
NOT SUFFICIENT

FINAL ANSWER IS (A)

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ArunSharma12 · Answer

If a light bulb is selected at random from a shipment, what is the probability that the light bulb is defective?

(1) The ratio of the number of defective light bulbs to the number of nondefective light bulbs is 1 to 60.

(2) The shipment contains 720 light bulbs.

probability that the light bulb is defective = number of defective light bulbs/ total number of light bulbs

statement 1:

defective bulbs/ non-defective bulbs = 1/60
defective bulbs = x, total bulbs = x + 60x = 61x
Probability = 1/61

statement 2:
total bulbs = 720
number of defective bulbs not known
not sufficient

Ans: A

GMATinsight · Answer

Question: Probability of Defective  = \frac{Defective-Bulbs }{ Total-Bulbs-in-Shipment} = ?

Statement 1 : The ratio of the number of defective light bulbs to the number of nondefective light bulbs is 1 to 60.

Defective / Non-defective = 1/60

i.e. Probability of Defective / Total = 1/61

SUFFICIENT

Statement 2 : The shipment contains 720 light bulbs

Total Defective bulbs in shipment is unknown hence

NOT SUFFICIENT

Answer: Option A

monikakumar · Answer

If a light bulb is selected at random from a shipment, what is the probability that the light bulb is defective?

(1) The ratio of the number of defective light bulbs to the number of nondefective light bulbs is 1 to 60.

(2) The shipment contains 720 light bulbs.
1) 1/61 is prob of defective lights
2) insufficient
Ans A

globaldesi · Answer

1) Ratio of defective to non defective is 1:60
hence defective to total is 1:60
thus probability is 1/60
sufficient

2)total bulbs = 760
this does not give any break up of defective and non defective
Cant deduce thus not sufficient

Hence A

madgmat2019 · Answer

what is the probability that the light bulb is defective.............

(1) The ratio of the number of defective light bulbs to the number of nondefective light bulbs is 1 to 60..........
no.of defective light bulbs can be x and total no.of bulbs can be 60x
then prob of selecting the light bulb is defective = xc1/60xc1 = 1/60....................sufficient

(2) The shipment contains 720 light bulbs.................clearly insufficient

OA:A

jrk23 · Answer

C is the answer. As probability is no.of defective bulb / total no. of bulb..

from b we will get the total no of bulb so "C" is the answer.

exc4libur · Answer

p(def/def+non)=?

(1) sufic
p=x/(x+60x)=1/61

(2) insufic

Ans (A)

If a light bulb is selected at random from a shipment, what is the pro

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GMAT Data Sufficiency (DS) Questions

If a light bulb is selected at random from a shipment, what is the pro

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