Answer:
7%
Explanation:
When trying to figure out percentages, we can try to use a proportional relationship. Percent means out of a hundred, and since we don't know the percentage on top, we can mark it as ?.
21/300 = ?/100
To figure this out quickly, we can try figuring out how many times we need to multiply or divide to get to the next number. Between 21 and ?, we can't do anything because we are unsure of what ? is.
Between 300 and 100, we can notice that to get to 100, we must divide by 3. 300/3 = 100
This means that the first ratio is three times the amount of the second ratio, which means that the second ratio is 1/3 of the first.
We can multiply 21 by 1/3 (or divide by 3), which will get us to 7.
7/100 = 0.07 = 7%