In a sequence of numbers, a4=12, a5=14, a6=16, a7=18, and a8=20. Which equation can be used to find the nth term of the sequence, an?

an=2n+12

an=3n+12

an=3n

an=2n+4

The answer is an=3n+12

When rates are expressed as a quantity of 1, such as 2 feet per second or 5 miles per hour, they are called unit rates. if you have a multiple-unit rate such as 120 students for every 3 buses, and want to find the single-unit rate, write a ratio equal to the multiple-unit rate with 1 as the second term.