21/70 = 30%
A value like 21/70, or 30%, can show up in everyday situations such as a sale, a survey, or a class grade. For example, if 30 out of every 100 shoppers choose a certain product, that is about the same proportion.
You can picture 30% quickly as three parts out of ten. It is a little less than one-third, so estimating it as “about a third” can help you understand its size.
A common mistake is thinking 30% means 30 out of 70, since the fraction includes 21 and 70. The denominator shows the total amount, so the fraction represents 21 parts out of 70 equal parts.
