SA= bh+2ls+lw
SA= 26*10 +40*26(2)+40*10
SA=260+1040(2)+400
SA=260+2080+400
SA=2740
<h3>
Answer: 39</h3>
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Explanation:
You can use the nCr formula shown below

where n = 39 and r = 1. However, you could also use the identity

which basically says there are n ways to pick 1 item if you are given a choice of n items. In this specific case, we have 39 items total, and there are 39 ways to pick one item.
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.
x - y = 16
x^2 + x^2 = 130
----------------
x^2 - y^2 = 256
+(x^2 + y^2 = 130)
2x^2 = 386
x^2 = 193
x = <span>13.892 (3DP)
----
</span>x - y = 16
13.892 - y = 16
-y = 2.108
y = -2.108
The numbers are: 13.892 and -2.108
Answer:
volume
Step-by-step explanation: