Question

How many seconds are there in a year?

Answer 1

Hint: We need to find out the number of seconds in a year. We start to solve the given question by finding out the number of seconds in a single day. Then, we need to multiply the number of seconds in a single day with the number of days in a year to get the desired result.

Complete step by step solution:
We will be using the Unitary method where we first find out the number of seconds in a single day and then find the number of seconds in a year by simply multiplying against the number of seconds in a day.

We know that one year has 365 days which means we need to find the number of seconds in 365 days.

We know that one minute has 60 seconds, one hour has 60 min, one day has 24 hours.
The number of seconds in a day is given by

$=60\times 60\times 24$

$=86400$

From the above, we know that there are 86400 seconds in a single day. So, we have

$\Rightarrow 1\text{ day = 86400 seconds}$

$\Rightarrow 365\text{ days = ?}$

Here, we perform cross multiplication to find out the number of seconds in a year. On cross multiplying, we get,
${\displaystyle \frac{365\times 86400}{1}}$
Simplifying the above expression, we get,
$31,536,000\text{ seconds}$
$\therefore$ There are 31,536,000 seconds in a year.

Note: Here in our question, we have used the unitary method. While writing our values from the question in a unitary form, for simplification, always write the things to be calculated on the right-hand side and things known on the left-hand side. We can also use the ratio and proportion method to solve this question. Never forget to write the units of the quantity after the whole evaluation of the question. Units are what defines a quantity.