Hi thumb, :)
There are 5 steps to answering this:
Step 1) How many seconds are in an hour? You know there's 60 seconds in a minute, and 60 minutes in a hour.
$${\mathtt{60}}{\mathtt{\,\times\,}}{\mathtt{60}} = {\mathtt{3\,600}}$$
Step 2) Find out how many in a day. There's 24hr in a day.
$${\mathtt{3\,600}}{\mathtt{\,\times\,}}{\mathtt{24}} = {\mathtt{86\,400}}$$
Step 3) So that's how many in a day, now there's 365 days in a year.
$${\mathtt{86\,400}}{\mathtt{\,\times\,}}{\mathtt{365}} = {\mathtt{31\,536\,000}}$$
Step 4) There's 10 years in a decade
$${\mathtt{31\,536\,000}}{\mathtt{\,\times\,}}{\mathtt{10}} = {\mathtt{315\,360\,000}}$$
Step 5 ) That's your answer 315360000 seconds.
-MathsGod1
