Answer:
The standard deviation is 2.6832815729997
Step-by-step explanation:
SD^2=(12-12)^2+...+(14-12)^2/10
SD^2=72/10
SD^2=7.2
SD=squeare root of 7.2
SD=2.6832815729997
Answer: 6 pieces
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Explanation:
3/4 = 6/8 after multiplying both parts by 2
We have a ribbon that is 6/8 of an inch long. We want to cut it into 1/8 inch pieces. We can see there will be exactly 6 pieces
Note how 6*(1/8) = 6/8
Or we can think of it as "we have a ribbon that is 6 units long and we want to cut it into pieces that are 1 unit each, so we'll have 6 pieces total". Replace "unit" with "1/8 inch" and you'll have the same idea.
0.43 oz
Hope this helps...
The answer is 28 years
At = A0 * e^(-k * t)
At = 12 g
A0 = 15 g
k = 7.9 × 10^-3 = 0.0079
t = ?
12 = 15 * e^(-0.0079 * t)
12/15 = e^(-0.0079 * t)
0.8 = e^(-0.0079 * t)
Logarithm both sides (because ln(e) = 1:
ln(0.8) = ln(e^(-0.0079 * t))
ln(0.8) = (-0.0079 * t) * ln(e)
-0.223 = -0.0079 * t
t = -0.223 / -0.0079
t = 28.23
t ≈ 28 years