(3+4) (40+3) (30+4)
= 7 + 47 + 34
= (7+47) +35
= 54 + 35
= 89
If it is not an integer, it would have to be a decimal.
Speed of the plane: 250 mph
Speed of the wind: 50 mph
Explanation:
Let p = the speed of the plane
and w = the speed of the wind
It takes the plane 3 hours to go 600 miles when against the headwind and 2 hours to go 600 miles with the headwind. So we set up a system of equations.
600
m
i
3
h
r
=
p
−
w
600
m
i
2
h
r
=
p
+
w
Solving for the left sides we get:
200mph = p - w
300mph = p + w
Now solve for one variable in either equation. I'll solve for x in the first equation:
200mph = p - w
Add w to both sides:
p = 200mph + w
Now we can substitute the x that we found in the first equation into the second equation so we can solve for w:
300mph = (200mph + w) + w
Combine like terms:
300mph = 200mph + 2w
Subtract 200mph on both sides:
100mph = 2w
Divide by 2:
50mph = w
So the speed of the wind is 50mph.
Now plug the value we just found back in to either equation to find the speed of the plane, I'll plug it into the first equation:
200mph = p - 50mph
Add 50mph on both sides:
250mph = p
So the speed of the plane in still air is 250mph.
Answer:
50
Step-by-step explanation:
Which number is greatest?
2.89 times 10 Superscript negative 8
1.997 times 10 Superscript 2
8.9 times 10 Superscript negative 6
5 times 10 Superscript negative 6
Answer: A)There are 5 nonfiction books for every 9 fiction books in the library.
Step-by-step explanation: If you do the math you realize that there are clearly less nonfiction books than fiction books.
105/5=21 and after 21*9 lines up and to check your work than
5*21=105 and 9*21=189 it is not B because the smaller number 105 is in front of the ratio 105:189 and 5:9
