Question

A watch which gains uniformly is 3 minutes slow at noon on Sunday and is 3 minutes 48 seconds fast at 2 P.M. on the following Sunday What time it was correct ?

• A. 2 P.M. On Monday
• B. 2 P.M. On Tuesday
• C. 3 P.M. On Wednesday
• D. 1 P.M. On Thursday

Answer 1

Answer: (C)

3 P.M. On Wednesday

Total (extra) gain = 3 min + 3 min 48 sec
$\Rightarrow$ = 6 min 48 sec
Clock covers the extra time (408 sec) in 7 days and 2 hrs
So Clock moves 408 sec in 170 hrs
$\Rightarrow$ So 180 sec covers in $\Rightarrow \frac{170\times 60\times 60}{408}\times 180$
$\Rightarrow$ 270000 sec
or $\frac{270000}{3600}=75hrs$
$\Rightarrow$ 3 days and 3 hrs So clock was correct at 3 p.m. on Wedensday
Ans (C)