Let X = the 29% alloy and Y = the 60% alloy.
They want a total of 80kg, so you have X +Y = 80
Rewrite that to get X = 80-Y
You also want 0.20X + 0.60Y = 0.52(80)
Replace X with 80-y:
0.20(80-y) + 0.60y = 0.52(80)
Simplify:
16 - 0.20y + 0.60y = 41.6
Combine like terms:
16 +0.40y = 41.6
Subtract 16 from each side:
0.40y = 25.6
Divide both sides by 0.40
y = 25.6 / 0.40
y = 64
Now you have Y replace y with 80 in X = 80-Y
X = 80 - 64
X = 16
They need 64 Kg of the 60% alloy and 16 Kg of the 20% alloy.
Answer: you can run 6 miles
explanation: 8 2/5 divided by seven = 1.2 1.2x5 = 6
7/30 x 100 = approx 23.3%
Answer:

Step-by-step explanation:
Given : The formula for the area of a trapezoid with altitude k and bases m and n is 
We have solve for m .
Consider the given formula 
Multiply both side by
, we have,

Now subtract n both side, we have,

Thus, 
Answer:
69.12r square inches
Step-by-step explanation:
C = 2πr
= 2 x π x 11r
= 69.12r