Keep track of units. To convert the units of hours per year to hours per day, use the fact that there are 365 days in a year.
1.57 hours per day
Practice makes perfect
We are trying to find the hours per day that each adult spends online. We will divide the total hours adults spent online in one year by the amount of adults, and we will get an answer with the units of hours per year per adult.
Hours adults spent online per year/Amount of adults= 93billion hoursyear/163million adults
It will be easiest to divide these numbers if they are in scientific notation. Notice that 93 billion can be written as 93 000 000 000. That is, 93.0 * 10^9. Now, to finish putting this in scientific notation we need to shift the decimal one point over.
93.0 * 10^9 ⇒ 9.30 * 10^(10)Now, let's put 163 million in scientific notation. This can be written as 163 000 000. That is, 163.0 * 10^6. To finish putting this in scientific notation we need to shift the decimal two points over.
163.0 * 10^6 ⇒ 1.630 * 10^8
Now that our numbers are in scientific notation, we can divide them.
We have found that each adult spent 571 hours per year online. Now, we need to convert this to the appropriate units — hours per day.
hours/year ⇒ hours/day
Note that there are 365 days in a year, so to convert to the units of hours per day per adult, we need to divide 571 by 365 days per one year.
571 hours/year * 1 year/365days = 1.57 hours/day
We have found that each adult spent 1.57 hours per day online over the duration of a year.
