Question

A tired worker slept at $7.45$ p.m. If he woke at $12$ noon, for how many hours did he sleep?

• A. $5$ hours $15$ min.
• B. $16$ hours $15$ min.
• C. $12$ hours
• D. $6$ hours $45$ min

Answer 1

The correct option is B $16$ hours $15$ min.

Time when worker sleep $=7.45$ P.M.
Time when he woke up $=12$ noon.
$\because$ Time period when he did not sleep in a day is between $12$ noon to $7.45$ i.e. for $7$ hr $45$ min.
$\therefore$ $24$ hours - $7$ hr $45$ min
$\Rightarrow$ $16$ hr $15$ min

or

Time for which he slept = (7.45 P.M. to 12 P.M.) + (12 P.M. to 12 noon)

$=4$ hr $15$ min $+12$ hr

$=16$ hr $15$ min

option B