Question

Reena’s mother said, to make idlis, you must take two parts of rice and one part urad dal. What percentage of such mixture would be rice and what percentage would be urad dal?

Answer 1

Hint: We will first find the fractions of portions used in idli of both urad dal and rice. After finding out the portion, multiply that fraction with 100 to get the required percentage of both the ingredients.

Complete step by step answer:
We are provided with the information that, we must take $2$ parts of rice and $1$ part of urad dal to make idlis as per the recipe of Reena’s mother.
Therefore, the total parts which are combining to form idli are $2 + 1 = 3$ parts.
Since 2 of these parts are covered with rice.
Therefore, rice is taken in $\dfrac{2}{3}$ portion. (Because portion is equal to parts of that ingredient used divided by the total parts).
Similarly, we have used one part of urad dal.
This implies that urad dal is taken in $\dfrac{1}{3}$ portion.
Now, if we multiply these portions by $100$, we will get the percentage of both the ingredients in the idlis.

Therefore, the percentage of rice used in idlis is = $\dfrac{2}{3} \times 100 = 66.\bar 6\% $.
Similarly, the percentage of urad dal in idlis is = $\dfrac{1}{3} \times 100 = 33.\bar 3\% $.

Note:
These portions of both rice and urad dal basically represent that if we take one idli, it is made of rice and urad dal only, where rice’s quantity is twice to that of the urad dal.
The percentage is basically a relative value which indicates the hundredth parts of any quantity. Therefore, 100% expresses the entire thing and 1% represents the hundredth part of that thing. Similarly, 200% represents twice the entire thing.
The percentage can also be converted into decimals by dividing the percentage quantity by 100. So, if we convert 66.66….% into a fraction. Divide it by 100, we will get $\dfrac{2}{3}$. Similarly, if we convert 33.33….% into a fraction. Divide it by 100, we will get $\dfrac{1}{3}$.