Math
posted by Grace .
An airplane traveled a distance d in t hours, where r>1, and arrived one hour late. The airplane would have arrived on time if it had traveled at what rate per hour?
a. t1
b. d/t1
c. d/t+1
d. d/t1
e. d/t+1

speed = distance/time.
its speed was d/t
on time its time would have been 1 hour less, so its speed would be d/(t1)