1. If we start with $300$ students and subtract 60 students, how many students remain? $300 - 60 =$ students.
2. If we start with $300$ students and subtract $20$ students three consecutive times, how many students remain?
$300-$ $-$ $-$
$=300-3\cdot$
$=$
3. Is one decrease of $60$ students the same as three decreases of $20$ students?