Question

kyle brought some crackers to school to share with his friends. he brought a box that was \\(\frac{8}{10}\\) full. when everyone had eaten, there was \\(\frac{5}{100}\\) of a box left.

what fraction of the box did the students eat?

select options below

1. the best operation to solve this problem is _______________.
2. the expression to model this problem is _______________.
3. the students ate _______________ of the box of crackers.

Explanation:

Identify the operation

To find the fraction eaten, we subtract the remaining amount from the starting amount.
Using the Word Problems knowledge point, we identify subtraction as the correct operation.

Write the expression

The starting fraction is \(\frac{8}{10}\) and the remaining fraction is \(\frac{5}{100}\).
The expression modeling this subtraction is:

$$\frac{8}{10} - \frac{5}{100}$$

Find a common denominator

Using the Common Denominators knowledge point, we convert \(\frac{8}{10}\) to have a denominator of \(100\):

$$\frac{8 \times 10}{10 \times 10} = \frac{80}{100}$$

Subtract the fractions

We subtract the numerators over the common denominator:

$$\frac{80}{100} - \frac{5}{100} = \frac{75}{100}$$

Simplify the fraction

We divide the numerator and denominator by their greatest common factor, \(25\):

$$\frac{75 \div 25}{100 \div 25} = \frac{3}{4}$$

Answer:

Question 1

The best operation to solve this problem is <blank>subtraction</blank>.

Question 2

The expression to model this problem is <blank>\(\frac{8}{10} - \frac{5}{100}\)</blank>.

Question 3

The students ate <blank>\(\frac{3}{4}\)</blank> of the box of crackers.