B. 2h+4
"Worked four hours MORE"
More symbolizes addition
"TWICE the number of hours"
Twice means multiple by two - two times a number
Answer:
The answer is -22
Step-by-step explanation:
remove the parentheses then you have 11 * -2 = -22
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Answer:
P = 0.006
Step-by-step explanation:
Given
n = 25 Lamps
each with mean lifetime of 50 hours and standard deviation (SD) of 4 hours
Find probability that the lamp will be burning at end of 1300 hours period.
As we are not given that exact lamp, it means we have to find the probability where any of the lamp burning at the end of 1300 hours, So we have
Suppose i represents lamps
P (∑i from 1 to 25 (
> 1300)) = 1300
= P(
> 
) where represents mean time of a single lamp
= P (Z> 
) Z is the standard normal distribution which can be found by using the formula
Z = Mean Time () - Life time of each Lamp (50 hours)/ (SD/
)
Z = (52-50)/(4/
) = 2.5
Now, P(Z>2.5) = 0.006 using the standard normal distribution table
Probability that a lamp will be burning at the end of 1300 hours period is 0.006
Answer:
12
Step-by-step explanation:
A rhombus is a parallelogram with all four sides equal.
Its diagonals are perpendicular.
Each of the triangles formed by the diagonals and the sides are congruent, so the area of the rhombus is 4 times the area of one of the triangles.
Since the short diagonal is given as 4, each of the triangles can be viewed as having a base of 2. Each triangle's height, h, then is one half the length of the long diagonal.
The are of one of the triangles is 1/2 (base)(height)=(1/2)(2)h
The area of the rhombus is then
4(1/2)(2)h=24
Solving for h gives
h=6
This makes the length of the long diagonal 2h=12
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