At the beginning of a lesson, a piece of chalk is 4.875 inches long. at the end of the lesson, it is 3.125 inches long. writ the two amounts in expanded form using fractiones.

Each digit of each amount is written in expanded form depending on the position of the digit.

Let's see number 4.875.

Digit 4 is in the place of the units so it is 4 * 1

8 is in the place of the tenths, so it is 8/10 = 8 * 1/10

7 is in the place of the hundreths, so it is 7/100 = 7 * 1 /100

5 is in the place of the thousanths, so it is 5/1000 = 5 * 1 / 1000

So, the number 4.875 written in expanded form using fractions is:

4*1 + 8 * 1/10 + 7 * 1/100 + 5 * 1/100.

Now, see the next amount, 3.125, which using the same procedure leads to:

3 *1 + 1 * 1/10 + 2 * 1/100 + 5 * 1/ 1000

Bis the correct answer