Answer:
1568
Step-by-step explanation:
The computation of the minimum sample size is shown below:
Given that
Error E = 11
The population standard deviation
=217
Confidence level 1-α = 95%
Now following formula should be used
n > (Zalpha ÷ 2 × sigma ÷ E)^2
As we know that
Zalpha ÷ 2= 1.96
Now the sample size is
n> (1.96 × 202 ÷ 10)^2
= 1568
The amount of gold coating in millimeters needed for the ring is the difference between the total coating and the coating that has already been applied. From the given above, that would be,
0.03 mm - 0.021 mm = 0.009 mm
Thus, the answer to this question is letter B.
Suppose the larger pump alone can empty the tank in L hours, and the smaller pump can finish the job in S hours, then each hour the large pump empties 1/L portion of the tank, and the small pump empties 1/S per hour
Working together for three hours, they empty the whole tank, which is 100% of it, so 3/L+3/S=100%=1
Larger pump can empty the tank in 4 hours less than the smaller one, so L=S-4
replace L: 3/(S-4)+3/S=1
Make the denominator the same to solve for:
3S/[S(S-4)] +3(S-4)/[S(S-4)]=1
(3S+3S-12)/[S(S-4)]=1
(3S+3S-12)=[S(S-4)]
S^2-10s+12=0
use the quadratic formula to solve for S
S is about 8.6
The answer is not whole hour.

We have, Discriminant formula for finding roots:

Here,
- x is the root of the equation.
- a is the coefficient of x^2
- b is the coefficient of x
- c is the constant term
1) Given,
3x^2 - 2x - 1
Finding the discriminant,
➝ D = b^2 - 4ac
➝ D = (-2)^2 - 4 × 3 × (-1)
➝ D = 4 - (-12)
➝ D = 4 + 12
➝ D = 16
2) Solving by using Bhaskar formula,
❒ p(x) = x^2 + 5x + 6 = 0



So here,

❒ p(x) = x^2 + 2x + 1 = 0



So here,

❒ p(x) = x^2 - x - 20 = 0



So here,

❒ p(x) = x^2 - 3x - 4 = 0



So here,

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