Answer:
53.2 mph
Step-by-step explanation:
Mara's family travels 239.4 miles between the hours of 9:10 a.m. to 1:40 p.m.
1:40 p.m. is 13:40.
Thus, they traveled for
13 hours 40 minutes - 9 hours 10 minutes = 4 hours 30 minutes
that is
hours.
Use formula:

where
D = distance
r = rate
t = time.
In your case,
D = 239.4 miles
t = 4.5 hours
Hence,

Pemdas 1. parentheses: everything is already in parentheses. so next is exponents. 10×-2 is -20. and 10×6 is 60. so 4×-20 is the next step. it equals -80. and then 3×60 is 180. lastly,add -80 and 180 together. the answer should be 100 if i did that correctly.