If Ruth began a job and worked continuously until she finish

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If Ruth began a job and worked continuously until she finished, at what time of day did she finish the job?

(1) She started the job at 8:15 a.m. and at noon of the same day she had worked exactly half of the time that it took her to do the whole job.
(2) She was finished exactly 7.5 hours after she had started.

Why is Option C not the best option?

OA A

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by mbawisdom » Mon Mar 05, 2018 5:55 pm
lheiannie07 wrote:If Ruth began a job and worked continuously until she finished, at what time of day did she finish the job?

(1) She started the job at 8:15 a.m. and at noon of the same day she had worked exactly half of the time that it took her to do the whole job.
(2) She was finished exactly 7.5 hours after she had started.

Why is Option C not the best option?

OA A
(1) we know that she worked continuously so if at noon she had worked half her day (12:00 - 8:15 = 3 hr 45 min) she must have finished at 3:45 PM (add 3hr and 45 min to noon) - sufficient
(2) this is not sufficient - we need to know the start time and the length of work to find the finish time, here we only have the length of work - not sufficient

Answer is A.