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Odds |
2019-12-16 |
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From Craig:
I’d like to know what are the odds of a lotto machine giving out a specific 4 digit number as a quick pick?
I know there are 10,000 possible 4 digit combinations. So let’s say the number is 3587 what are the odds the lotto machine spits it out EXACTLY that way on a quick pick?
Answered by Penny Nom. |
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Input and output of a function |
2019-12-16 |
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From Destanie:
What is the output if the input is -1???
Answered by Penny Nom. |
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Some questions about sets |
2019-12-15 |
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From M.Azzi:
Hello,
(I) - In set theory can a given set contain both elements and subsets, as "elements", as in :
A = {1,2,{},3,{{3}},8}
If yes :
1 - then, is |A| = 6 ?
2 - if the empty set is a subset of every set,
2. 1. does {} = {{}}, {{{}}} etc? , and if the is true what are the respective cardinals of the latter three? (0,1,1?).
2 . 2. Why isn't {1} equal to {{},1}? and why should these two be equal without having the same cardinality?
Sorry if my questions are not well expressed.
Thank you for the great service you provide.
Answered by Harley Weston. |
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More on lampshades from a cone |
2019-12-14 |
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From Guy:
from an earlier post re; lampshade from a cone
Being math ignorant I cannot figure out how this equation makes sense
\[\frac{2\pi \times 33 - 2\pi \times 20}{2\pi \times 33} = \frac{13}{33}\]
imagine these as fractions multiplied by 360 to calculate a section of a circle to form a cone
Thx
Answered by Penny Nom. |
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A function problem |
2019-12-12 |
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From akash:
if (2,1) is on the f(x), what is the coordinate of the corresponding point of -2(f(2x-6)+5?
Answered by Penny Nom. |
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Guess and check |
2019-12-11 |
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From Mariajosé:
brian bought 98 stickers. the number of stickers per sheet was 2 times as large as the number of sheets. how many sheets did brian buy
Answered by Penny Nom. |
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The fencing needed for a square pasture |
2019-12-10 |
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From Penny:
I'm trying to calculate how many feet of fence I will need to fence a 4 acre square pasture.
Answered by Harley Weston. |
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Strings made from three characters |
2019-12-10 |
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From Kelley:
Hi,
I vaguely remember some formula for determining all the possible combinations of a set of numbers (or whatever).
If I have 3 numbers (0 - 2), then I have 0, 1, 2, 00, 01, 02, 10, 11, 12, 20, 21, 22, 000, 001, 002, 010, 011, 012, 020, 021, 022, 100, 101, 102 and so on.
What is the formula for determining all potential results?
Thank you!!
Kelley
Answered by Penny Nom. |
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The equation of a line |
2019-12-10 |
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From Jourdan:
Suppose a mining company will supply 96000 tons of ore per month if the price is 80 dollars per ton but will supply 70500 tons per month if the price is 20 dollars per ton. Assuming the supply function is of the form y = m x + b , find the slope, m and y-intercept, b
Answered by Penny Nom. |
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Roll two dice and record the difference |
2019-12-09 |
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From Barbara:
Suppose you roll two dice 100 times. Each time you record their difference
(always subtracting the smaller one from the bigger one to get a positive
difference). The possible values you get are 0,1,2,3,4 and 5. You record
the frequency of each value in the following table:
Difference of two dice 0 1 2 3 4 5
Observed frequency 12 31 26 13 10 8
Let your null hypothesis be that the dice are fair, and the alternative
hypothesis be that they are not fair. Using a confidence level of α = 0.10,
test the null hypothesis by a goodness-of-fit test.
Hint: begin by
completing table:
x 0 1 2 3 4 5
f(x)
Answered by Penny Nom. |
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Two people are clapping their hands |
2019-12-06 |
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From Yukti:
Two people are clapping their hands, but with different frequencies. Ramya claps her hands
17 times per 3 minutes, and Kumar claps his hands 31 times per 5 minutes. They start
clapping at the same time. How many times does each one clap before they clap together at
the same time again?
Answered by Penny Nom. |
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3/8 and 0.375 |
2019-12-05 |
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From Zamyiah:
how does 3/8 turn into 0.375 i just don't understand it the question is hard. please answer in time thank you for your time.
Answered by Penny Nom. |
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Sigma notation |
2019-12-04 |
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From Kenneth:
What would be used for the top and bottom indices for the sigma sign in my example shown below?
If the amounts were 1 + 2 + 3, the top index would be 3 and the bottom would be i = 1, but if the amounts are 1 + 2 + 4, or 1 + 0.05 + 1/3, what would the indices be since these amounts are in an uneven pattern.
I thank you for your reply and explanation
Answered by Harley Weston. |
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Combinations of cities |
2019-12-03 |
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From Oliver:
Hi!
I'm looking to find out how many combinations (non repeating) there are for 6 cities.
If we name the cities A to F, possible combinations would include;
A.
A, B.
B.
A, B, C.
A, C.
B, C.
C.
and so on.
Thank you!
Answered by Penny Nom. |
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Two digit numbers |
2019-12-03 |
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From Lacy:
Using the digits zero through nine, how many two-digit numbers can be formed,which do not have a four or five?
Answered by Penny Nom. |
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