How to u show this number 0.624 in expanded from

Which expression is equivalent to -12(3x-3/4)

Grandpa ernie is shrinking! over the past 4 years his height decreased by a total of 2.4 cm.it decreased by the same amount each year. what was the change in grandpa ernie's height each year

More than 450450 students traveled to a state park for a field trip. the school allowed 66 students to travel by car, and the rest traveled on 1111 buses, each of which held the same number of students. if there were ss students in each bus, which inequality best represents this situation?