Question

At a gas station, $53\text{ L 950 mL}$ of petrol was sold on Sunday, $975\text{ L}$ on Monday and $635.50\text{ L}$ on Tuesday. So, how much petrol was sold in total?

Answer 1

Hint: First we will write down all the values of petrol sold on all the three days and first we will convert millilitre to litres using conversion \[1~L=1000~mL={{10}^{3}}~mL\] and then we will add all the obtained values and ultimately obtain the answer we require.

Complete step-by-step answer:
This is a case of the metric system. To convert from "milli-" to the standard unit, such as meters or liters, we divide by $1000$ . One millilitre is equal to a thousandth of a litre, and one litre is equal to one thousand millilitres. In numbers, that is:
\[1~mL=0.001~L={{10}^{-3}}~L\]
\[1~L=1000~mL={{10}^{3}}~mL\]
Therefore,
On the first day that is on Sunday, the total petrol sold was $53\text{ L 950 mL}$ , we will first convert the millilitre into the litres, so we will divide $950\text{ mL}$ by $1000$ . Therefore: $\dfrac{950}{1000}=0.95$ , so the total petrol sold on Sunday is $53+0.95=53.95\text{ L}$.
On Monday the total petrol sold as given in the question is $975\text{ mL}$
And finally it is given in the question that the total petrol sold on Tuesday is $635.50\text{ L}$
So we have to find out the total petrol sold therefore we will add the values of petrol sold on all the three days that is Sunday, Monday and Tuesday
Therefore: $53.95+975+635.50=1664.45\text{ L}$

Hence, the total petrol sold will be $1664.45\text{ L}$ .

Note: We should be careful while converting the metric system as sometimes students can instead of dividing the millilitre by 1000 we may get confused by dividing the millilitre by 100 because when we convert centimetres to metre we divide it by 100 .