An adventure park charges $16 per adult and $10 per child (6 - 16 years) to enter the park. Melissa, who is 9, and her five family members, (2 adults and 3 more children) went to the park. Melissa's dad paid with a one-hundred dollar bill. How much change did her dad get back after he paid the park entrance fees?

Total charge at park, T = 2×charge on adults + 4×charge on children .

T =$(2×16 + 4×10)

T = $72

Now, Melissa's father paid $100 .

Amount her father get back is :

A = $( 100 - 72 )

A = $28

Therefore, her father get $28 back.

Hence, this is the required solution.

Let x and (442-x) represent the distance of the trains traveled. X/90 mph=442-x/80 mph
Cross multiply 80×x =90(442-x)
80x=90×442-90x
170x=90×442
X= 90×442/170
X=234, distance traveled by train going 90mph
234mi/90mph = 2.6 hr, time it takes for the two trains tok meet.
Checking your
90×2.6+80×2.6=234mi+208mi = 442mi