P = 2w + 2l where w is the width, and l is the length. We know the length (l) is 3 inches longer than it's width (or l = w+3). Substitute w +3 into Perimeter equation. P = 2w + 2(w+3).
X = 10
The triangles are similar by SAS, so we can set up a proportion of their sides.
9/(33-9) = 12/(3x+2)
9/24 = 12/3x+2
Reduce
3/8 = 12/3x+2
Cross multiply
3(3x+2) = 12*8
Distribute and multiply
9x + 6 = 96
Subtract 6
9x = 90
Divide by 9
x = 10
Check:
9/24 = 12/3x+2
9/24 = 12/3*10 + 2
9/24 = 12/30 + 2
9/24 = 12/32
3/8 = 3/8 :)
This kind of problems requires to add the working velocities. The total velocity is the sum of the individual velocities.
Anita's velocity = 1 pool/8 hours
Chao's velocity = 1 pool/6 hours
Combined velocity 1/8 + 1/6 = (3 + 4)/24 = 7/24 pool/hour
Time = 1 pool / (7/24) pool/hour = 24/7 hour =3.43 hours
Answer:
Mass of A = 5760 grams
Step-by-step explanation:
Surface area is given, so we can set-up a similarity equation to solve for k, proportionality constant. Here, we will relate both of them through k^2, because they are 2 dimensional (area). Thus
Surface Area of A = k^2 * Surface Area of B
28 = k^2 * 40.32
k^2 = 28/40.32
k^2 = 25/36
k = Sqrt (25/36)
k = 5/6
Now, we want to find mass (1 dimensional quantity), thus we can say:
Mass of A = k * Mass of B
Mass of A = (5/6) * (6912)
Mass of A = 5760 grams
