In an office the working hours are 9.30 AM to 4.30 PM and in between 30 minutes are spent on lunch. Find the ratio of office hours to the time spent for lunch.
A. \[14:1\]
B. \[1:14\]
C. \[7:30\]
D. \[30:7\]

Hint: First of all, convert the timings into hours by using the conversion one hour is equal to sixty minutes. Then find the ratio of office hours to the time spent for lunch. So, use this concept to reach the solution of the problem.

Complete step-by-step answer:
The total working office hours are 9.30 AM to 4.30 PM \[ = 7{\text{ hours}}\]
Converting the working office hours into minutes by using the conversion 1 hour = 60 minutes
\[ \Rightarrow 7{\text{ hours}} = 7 \times 60 = 420{\text{ minutes}}\]
The time spent for lunch \[ = 30{\text{ minutes}}\]
So, the ratio of office hours to the time spent for lunch \[ = 420:30 = 14:1\]
Thus, the correct option is A. \[14:1\]

Note: Here we have converted the office working hours into minutes because the time spent for lunch is given in minutes. We can do vice-versa i.e., we can convert the time spent into hours (which is equal to half an hour) and then we can find the ratio of office hours to the time spent for lunch.