Answer: d
Step-by-step explanation:
The probability of not being purple is the probability of the three other colors. Suppose the number of purple marbles is x. Then we have 20+30+40+x = 90 + x marbles. Then the probability of not being purple is 90/(90+x). If this fraction can have a lowest term for some value of x, then the numerator of this lowest term must be a factor of 90.
Checking through the options, only option D has a non-factor of 90 as its numerator.
Complete question:
The manager of a supermarket would like to determine the amount of time that customers wait in a check-out line. He randomly selects 45 customers and records the amount of time from the moment they stand in the back of a line until the moment the cashier scans their first item. He calculates the mean and standard deviation of this sample to be barx = 4.2 minutes and s = 2.0 minutes. If appropriate, find a 90% confidence interval for the true mean time (in minutes) that customers at this supermarket wait in a check-out line
Answer:
(3.699, 4.701)
Step-by-step explanation:
Given:
Sample size, n = 45
Sample mean, x' = 4.2
Standard deviation 
= 2.0
Required:
Find a 90% CI for true mean time
First find standard error using the formula:
Standard error = 0.298
Degrees of freedom, df = n - 1 = 45 - 1 = 44
To find t at 90% CI,df = 44:
Level of Significance α= 100% - 90% = 10% = 0.10
Find margin of error using the formula:
M.E = S.E * t
M.E = 0.298 * 1.6802
M.E = 0.500938 ≈ 0.5009
Margin of error = 0.5009
Thus, 90% CI = sample mean ± Margin of error
Lower limit = 4.2 - 0.5009 = 3.699
Upper limit = 4.2 + 0.5009 = 4.7009 ≈ 4.701
Confidence Interval = (3.699, 4.701)
The volume equals length x width x height so multiply all of those with a calculator and you’ll get your answer hope I helped :)
Answer:
56.25%
Step-by-step explanation:
800 - 350 = 450
1% of 800 = 8 (800 divided by 100)
450 divided by 8 = 56.25
Answer:
x squared plus 2x minus 1.
Step-by-step explanation:
x3+3x2+x-9 is in the division "house" and x-1 is on the outside. xsquare times x equals x cubed. and x square times negative 1 equals -x squsre. put x square on top of the roof. change the signs. the x cubed cancels out. and bring down 2x square from subtracting 3x square and -x square and bring down the x-9. Put 2x on top of the roof too and 2x times x equals 2x square and multiply by -1. U will have 2x square -2x square and -2x plus x which equals -1x cuz the 2x square cancels out. bring down the -9. Now i have -1x-9. Multiply by -1 and put -1 on the roof. -1x+1x cancels out. and -1 times -1 equals positive 1. So -9+1=8. U van do any further cause as soon as the last number is at the end of the roof and u cant go further, ur done dividing. so the answer is x square+2x-1/×-1 +8 as the remainder. hope i helped
