Question

a school book fair has 300 books and 10% are mystery novels. partition the double number line to find 10% of 300.
books
0
300
0%
100%

Explanation:

Step1: Understand the double number line

The bottom number line is for percentages (0% to 100%) and the top is for the number of books (0 to 300). We need to find 10% of 300.

Step2: Relate percentage to number of books

Since 100% corresponds to 300 books, to find 10% we can divide the total number of books by 10 (because 10% is $\frac{10}{100}=\frac{1}{10}$ of 100%). So we calculate $300\times\frac{10}{100}$ or $300\div10$.

Step3: Calculate the value

$300\times0.1 = 30$ (or $300\div10 = 30$). On the double number line, we can partition the percentage line into 10 equal parts (each 10%) and the books line will also be partitioned into 10 equal parts, each part being 30 books (since $300\div10 = 30$).

Answer:

10% of 300 is 30. So on the double number line, the mark for 10% on the percentage line will correspond to 30 on the books line.