Find the unknown number in the equation. 12-4=1+?+1

:24% of students in a class are girls. if there are less than 30 students in this class, how many students are there? how many girls are there?

What number is 7 units left of -15?

Traffic on saturday, it took ms. torres 24 minutes to drive 20 miles from her home to her office. during friday's rush hour, it took 75 minutes to drive the same distance. a. what was ms. torres's average speed in miles per hour on saturday? b. what was her average speed in miles per hour on friday?