Answer:
25000m/s
Step-by-step explanation:
The following formula is used to calculate the speed or velocity of a wave.
V = f * w
Where V is the velocity (m/s)
f is the frequency (hz)
w is the wavelength (m)
First, determine the frequency.
Calculate the frequency of the wave.
Next, determine the wavelength.
Calculate the wavelength of the wave.
Finally, calculate the wave speed.
Using the formula above, calculate the wave speed.
Let's say:
lengh=x
width=y
"The length of a rectangle is 4 inches greater than the width."
That means: x=y+4 (in inches).
the parameter is (by definition) 2*lenght+2*width.
so we have 2*x+2y=24.
we also know that x=y+4
Substituting:
2*(y+4)+2y=24.
2*y+8+2y=24
4*y+8=24//substitute 8 from both sides
4*y=16//dividing both sides by 4.
y=4
So the width is 4!
The lenght is y+4=8!
the dimensions are 4 by 8.
(check: 2*4+2*8=24, correct!)
Answer:
16 bags for the first(30% pure) and 64 bags of the second(80% pure)
Step-by-step explanation:
If they are mixed in a ratio of x bags to y bags
(0.3x+0.8y)/(x+y) = 0.7
0.3x + 0.8y = 0.7(x+y)
Multiply both sides with 10
3x + 8y = 7(x+y)
4x = y ——(1)
x + y = 80 ——(2)
Solve simultaneously
x + 4x = 80
5x = 80
x = 16 bags
y = 4x = 64 bags
The answer to this problem is 21/16