The bicycle`s speedometer measures the speed to the nearest 0.1 mph. So 17.15 mph is not appropriate way to report speed, because then it should measure speed to the nearest 0.05 mph. Also 17 mph and 20 mph are whole numbers and it does not have to be so accurate.
Answer: B. 17.1 mph
SOLUTION
Write out the denominator of the fraction, we have
We want to obtain the least common denominator.
To do this, we need to factorize each of the expression given
Then we factorise the other fraction using difference of two square
The the factorise expression becomes
To obtain the least common denominator, we select the common factor and the product of the other factor,
Hence
Thus
The Least Common Denominator is (x +3)(x+3)(x-3) (Last Option )
square root 27 is 3square root 3 so the answer is 2 square root three
The product is the result of an multiplication which means when have to multiply:
6 * 5 * m = 30m
The multiplication ends there since there is no given value for m.
Hope it helped,
Happy homework/ study/ exam!
Var[2X + 3Y] = 2² Var[X] + 2 Cov[X, Y] + 3² Var[Y]
but since X and Y are given to be independent, the covariance term vanishes and you're left with
Var[2X + 3Y] = 4 Var[X] + 9 Var[Y]
X follows an exponential distribution with parameter <em>λ</em> = 1/6, so its mean is 1/<em>λ</em> = 6 and its variance is 1/<em>λ</em>² = 36.
Y is uniformly distributed over [<em>a</em>, <em>b</em>] = [4, 10], so its mean is (<em>a</em> + <em>b</em>)/2 = 7 and its variance is (<em>b</em> - <em>a</em>)²/12 = 3.
So you have
Var[2X + 3Y] = 4 × 36 + 9 × 3 = 171
