Write a proportion that could be used to solve for each variable.
Then solve.
2.7 centimeters in 3 seconds
x centimeters in 4 seconds
a. 2.7/3 = x/4; x = 3.3 c. 2.7/4 = x/3; x = 2
b. 2.7/3 = 4/x; x = 4.4 d. 2.7/3 = x/4; x = 3.6