M = hours driven by Maria
c = hours driven by Carlos
since we know that Carlos was driving at an average of 52 mph, then in 1 hour he drove 52 miles, in 2 hours he drove 2*52 miles in "c" hours he drove c*52 miles or
52c.
Maria on the other hand is faster and does 54 mph, in 1 hour she does 1 * 54 miles, and on 2 hours she does 2 * 54 miles and in "m" hours she does m * 54 miles or
54m.
now, we know the total amount of miles they both drove is 217, so whatever "m" and "c" are we know that
54m + 52c = 217.
we also know it took 4.1 for the whole trip, so
m + c = 4.1.

so Maria drove for 1.9 hours.
How many hours did Carlos drive for? well, c = 4.1 - m.
19/25 or 76/100 so it would be 76%
Answer: 42
Step-by-step explanation:
36+42 = 78
6(6) =36+42 (like in the equation) =78
Answer:
-0.4x - 0.30 or 
Step-by-step explanation:
Change all the fractions to decimals.
-2/5 = -0.4 Distribute that over x and 0.8 1/50 = 0.02
you get -0.4x -0.32 + 0.02
Change all the decimals to fractions.
0.8 is 8/10 so -2/5 times 8/10 is -16/50
-2x/5 - 16/50 + 1/50 add or subtract the fractions to get -15/50 Then reduce (÷5)
-2x/5 - 3/10