Answer:
Now: 6 yr mean age
in 10 yrs? 16 yr mean age
in 20 yrs? 26 yr mean age
Why? Because regardless of the relationship between each sibling's age, your always adding the 10yrs to each individual, which you are then dividing out to determine the mean age. See proof below:
Including anita, there are 6 people. We'll define each age as an unknown variable. Assume we know nothing about the relationships between their ages
for example sake
anita's age = a
sister 1's age = b
sister 2's age = c
brother 1's age = d
brother 2's age = e
brother 3's age = f
Now:
mean age = (a + b + c + d + e + f)/(6 people) = 6 yrs
in 10 yrs:
mean age = ((a+10) + (b+10) + (c+10) + (d+10) + (e+10) + (f+10))/(6 people)
mean age = (a + b + c + d + e + f + 60)/(6 people)
mean age = (a + b + c + d + e + f)/(6 people) + (60)/(6 people)
mean age = (a + b + c + d + e + f)/(6 people) + 10
Notice the first term is the same expression of the mean age for "Now"
Thus, in 10 yrs:
mean age = 6 + 10 = 16 yrs
The same principle applies for "x" yrs from now, as long as we know what the mean age is "Now"
2 to the fifth power over 3 squared all raised to the fourth power
Answer: 2 to the twentieth power over 3 to the eighth power
Used:
Answer:
12.81 miles
Step-by-step explanation:
You need to use the Pythagorean Theorem to draw a triangle.
10 squared + 8 squared = c squared.
100 + 64 = c squared
164 = c squared
find the square root of 164:
12.81.
49. From 3 coin tosses, there are 8 possible outcomes:
... TTT, TTH, THT, THH, HTT, HTH, HHT, HHH
All but the first have at least one head, so 7/8 of the possibilities have at least one head. That's 87.5% (not among your choices).
Likewise, all but the last listed outcome have at least one tail. The problem is symmetrical that way when the coin is fair. 87.5% of outcomes have at least one tail.
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Perhaps you can tell I read your question as having two parts. If your question is the probability of getting at least one head AND at least one tail, you can see that condition includes 6 of the 8 outcomes, or 75%, matching selection d.
50. See for yourself: the calculator says 66.82%. Your best choice is selection d.
