Slow clock — from Monday 7:00 a.m. to “Friday 6:00 a.m.” (shown): A clock is correct at 7:00 a.m. on Monday but loses 15 minutes every 24 hours. When this slow clock shows 6:00 a.m. on the following Friday, what is the true time and weekday?

Introduction / Context:
This is a “gain/loss” clock problem. The clock loses 15 minutes per 24 hours, so its indicated time runs slow relative to true time. We must map a shown (indicated) time back to the true time.

Given Data / Assumptions:

• Clock correct at Monday 7:00 a.m. (start anchor).
• Loss rate = 15 minutes per 24 true hours.
• Clock shows Friday 6:00 a.m.; find true time then.

Concept / Approach:
If a clock loses 15 minutes in 24 hours, then in 24 true hours it shows only 23 h 45 m = 23.75 h. Thus indicated/true time ratio = 23.75/24 = 95/96. Equivalently, true time = indicated × (96/95). We first compute the indicated elapsed time from the anchor, then scale.

Step-by-Step Solution:
1) Indicated elapsed from Mon 7:00 a.m. to Fri 6:00 a.m.: 3 full days (Tue–Thu) = 72 h, plus Mon 7→Tue 7 = 24 h (now 96 h), but we need Fri 6 which is 1 hour earlier than Fri 7, so total indicated = 95 h.2) Convert to true elapsed: 95 × (96/95) = 96 h.3) True time = Monday 7:00 a.m. + 96 h = Friday 7:00 a.m.

Verification / Alternative check:
Over 4 days, the slow clock loses 4 × 15 = 60 minutes, i.e., it reads one hour behind. So when it reads 6:00 a.m., true is 7:00 a.m.

Why Other Options Are Wrong:
6:15 or 6:30 a.m. under-correct the one-hour deficit; 7:15 a.m. over-corrects.

Common Pitfalls:
Using 15/24 as hours directly without forming the ratio; forgetting to compute indicated elapsed time first.

Final Answer:
7 : 00 am Friday