Question

What time will be $2$ hours $50$ minutes after $9:10$AM?

Answer 1

Hint: The time shown in the watch is $9:10$ AM which is similar to $x:y$ where $x$ represent the hours and $y$ represent the minutes. We have to find the time shown by the watch after $2$hours and $50$ minutes so, $\left( {x + 2} \right)$ gives the value shown by hours hand and $\left( {y + 50} \right)$ gives the value shown by minutes hand of the watch. We know that $1$ hour$ = 60$min. if the value of $\left( {y + 50} \right)$ exceeds $60$ then the value shown by hours hand increases by $1$ and the value shown by minutes hand decreases by 60.

Complete answer:
Given, the time shown in the watch is $9:10$AM.
We have to find the time shown by the watch after $2$hours $50$minutes.
Now, add $2$ and $9$ which gives the time shown by the hours hand of the watch. And then add $10$ and 50 which gives the time shown by the minutes hand of the clock. This gives,
\[
  \,\,\,\,hrs\,\,\,\,\,\,\,\,\,\,\,\,\,\min \\
  \,\,\,\,09\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,10 \\
   + \,02\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,50 \\
  \,\,\,\,\overline {11\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,60} \\
 \]
We know that $60\min = 1hr$. So, if the value shown by minutes hand becomes equal or greater than 60 then add $1$ to the value shown by hours hand and subtract $60$ from the value shown by minute hand to get the required time.
So, the hour hand of the watch shows $\left( {11 + 1} \right) = 12$ and the minute hand shows $\left( {60 - 60} \right) = 00$min.

Thus, the required time is $12:00$AM.

Note: At $12:00$ we can say both AM and PM but if the time shown by the watch before $12:00$ is in AM then this is said as $12:00$AM but if the time shown before $12:00$ is in PM then this is said to be $12:00$.