Isabelle made this calendar to show the number of weeks until she leaves for vacation. She wants to write the number of weeks as a fraction. Isabelle writes the denominator as 1.

A calendar for the month of February is shown. There are four rows of seven on the calendar. Week 1 is labeled for days 1 to 7, week 2 is labeled for days 8 to 14, week 3 is labeled for days 15 to 21, and week 4 is labeled for days 22 to 28.

Since there are four weeks until Isabelle leaves for vacation, she can write this as a fraction with a denominator of 1:

4/1

To write the number of weeks as a fraction, we need to determine the numerator and denominator.

In this case, we know that there are four weeks in total. The denominator is given as 1.

Therefore, the fraction representing the number of weeks is 4/1.

To determine the number of weeks until Isabelle leaves for vacation, we need to count the number of weeks on the calendar.

From the given information, we can see that there are four rows of seven on the calendar. Each row represents a week, and each week contains seven days.

Therefore, we can conclude that there are four weeks in total on the calendar.

Since Isabelle wants to write the number of weeks as a fraction with the denominator as 1, we can express the number of weeks as 4/1.