A digital watch gains 5 minutes every 12 hours. It was set correctly to show the accurate time at9:00 a.m. on Tuesday. What will betheactual correct timewhen the watchshows9:00 a.m. on Thursday?

(a) 9:20 a.m.

(b) 8:40 a.m.

(c) 8:20 a.m.

(d) 9:40 a.m.

Question

A digital watch gains 5 minutes every 12 hours. It was set correctly to show the accurate time at9:00 a.m. on Tuesday. What will betheactual correct timewhen the watchshows9:00 a.m. on Thursday?

(a) 9:20 a.m.

(b) 8:40 a.m.

(c) 8:20 a.m.

(d) 9:40 a.m.

ONLiNE UPSC · Accepted Answer

The watch gains 5 minutes every 12 hours, so in 48 hours (from 9 a.m. Tuesday to 9 a.m. Thursday), it gains:
(48 &divide; 12) &times; 5 = 4 &times; 5 = 20minutes.

So, when the watch shows 9:00 a.m. on Thursday, the actual time is:
9:00a.m.&ndash;20minutes = 8:40 a.m.

Hence, option b is correct.

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