4 + 4 + 4 - 1 = 11? Was it supposed to be an equation? I am confused.
Answer:
6000.
Step-by-step explanation:
Hundreds digit is 6 so we round up the thousand digit (5) to get 6000.
The perimeter of any figure, is all its sides summed up
now, notice the picture below, using the 30-60-90 rule, that's "x"
now, get the other sides, since you know what "x" is, and sum them up, that's the perimeter
Let n = the hours elapsed when the two trains are 660 miles apart.
Let the first train travel east and the second train travel west.
The distance traveled by the first train is
x = (50 mi/h)*(n h) = 50n mi
The distance traveled by the second train is
y = (60 mi/h)*(n h) = 60n h
The distance between the two trains after n hours is
x + y = 50 n + 60n = 110n mi
Because this distance is 660 miles, therefore
110n = 660
n = 6 hours
Answer: 6 hours
I hope this helps. Sorry it took so long