Answer:
50.40% probability that all 4 are different.
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
Desired outcomes:
4 digits, all different
For the first digit, it can be any of them, so there are 10 possible
For the second digit, it can be any of them other than the first digit. So there are 9 possible.
For the third digit, it can be any of them, other than the first and the second. So there are 8 possible.
By the same logic, 7 possible digits for the fourth. So
Total outcomes:
4 digits, each can be any of them(10 from 0 - 9).
So
Probability:
50.40% probability that all 4 are different.
I think the answer should be divisible because you can’t really divide 1 without getting the same # your dividing by.
Hello from MrBillDoesMath!
Answer:
5.06
Discussion:
Angle J = 180 - (120 + 40) = 180 - 160 = 20 degrees,
From the law of sines
sin(120)/k = sin(20)/2 =>
sin(120) = k * ( sin(20)/2) ) (multiply both sides by "k")
k = sin(120)/ ( sin(20)/2) (divide both sides by sin(20)/2)
k = (0.866) / ( 0.171) = 5.06
Regards,
MrB
P.S. I'll be on vacation from Friday, Dec 22 to Jan 2, 2019. Have a Great New Year!
surface area (S) of a right rectangular solid is:
S = 2*L*W + 2*L*H + 2*W*H (equation 1)
where:
L = length
W = width
H = height
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you have:
L = 7
W = a
H = 4
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formula becomes:
S = 2*7*a + 2*7*4 + 2*a*4
simplify:
S = 14*a + 56 + 8*a
combine like terms:
S = 22*a + 56
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answer is:
S = 22*a + 56 (equation 2)
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to prove, substitute any value for a in equation 2:
let a = 15
S = 22*a + 56 (equation 2)
S = 22*15 + 56
S = 330 + 56
S = 386
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since a = 15, then W = 15 because W = a
go back to equation 1 and substitute 15 for W:
S = 2*L*W + 2*L*H + 2*W*H (equation 1)
where:
L = length
W = width
H = height
-----
you have:
L = 7
W = 15
H = 4
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equation 1 becomes:
S = 2*7*15 + 2*7*4 + 2*15*4
perform indicated operations:
S = 210 + 56 + 120
S = 386
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surface area is the same using both equations so:
equations are good.
formula for surface area of right rectangle in terms of a is:
S = 22*a + 56
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