Put the values of m and p to the expression:
80 miles per hour is 128.74752 kilometers per hour
Y=-x+9 is the correct answer
I'm terrible at math, so I'm sorry if I'm totally wrong, but I'm assuming you just take the average:
20+28=48m
48/2=24m
On average, it may take them 24m if they work together.
I don't speak Spanish but I think that this is what you meant:
80 * 2/5 = 32
so 2/5 of 80 % is 32 % (80/5 * 2)