Question

A sugar bag contains $30{\text{kg}}$ of sugar. After consuming $\dfrac{2}{3}$ of it, how much sugar is left in the bag?

Answer 1

Hint: Here we can find the sugar that is consumed by multiplying $\dfrac{2}{3}$ by $30$ and we will get the weight of the sugar consumed. Now we can subtract this amount from the total sugar we have to get the amount of sugar that is left in the bag.

Complete Step by Step Solution:
Here we are given that there is a total of $30{\text{kg}}$sugar in the sugar bag. Now we are also given that $\dfrac{2}{3}$ of the total sugar has been consumed which means that we can find the amount of sugar that is consumed by multiplying $\dfrac{2}{3}$ by $30$
So we will get:
Total amount or weight of the sugar that has been consumed is equal to \[\dfrac{2}{3}\left( {30} \right) = \left( 2 \right)\left( {10} \right) = 20{\text{kg}}\]
Now we have got the total amount of sugar that has been consumed and also we have the total amount of the sugar that is contained in the sugar bag. Hence we can subtract the total amount and the sugar that is consumed to get the leftover sugar in the bag.
So we can say that:
${\text{sugar left}} = {\text{total sugar}} - {\text{sugar that is consumed}}$
Now we can substitute the respective values in the above formula and we will get:
${\text{sugar left}} = \left( {30 - 20} \right){\text{kg}} = 10{\text{kg}}$

Hence we can say that sugar left is $10{\text{kg}}$

Note:
Here the student can also say that as $\dfrac{2}{3}$ of the sugar is consumed $\dfrac{1}{3}$ is left. Directly we can multiply this $\dfrac{1}{3}$ with $\left( {30} \right)$ and get the $10{\text{kg}}$ sugar that is left.