Answer:
a) the probability that the minimum of the three is between 75 and 90 is 0.00072
b) the probability that the second smallest of the three is between 75 and 90 is 0.396
Step-by-step explanation:
Given that;
fx(x) = { 1/5 ; 50 < x < 100
0, otherwise}
Fx(x) = { x-50 / 50 ; 50 < x < 100
1 ; x > 100
a)
n = 3
F(1) (x) = nf(x) ( 1-F(x)^n-1
= 3 × 1/50 ( 1 - ((x-50)/50)²
= 3/50 (( 100 - x)/50)²
=3/50³ ( 100 - x)²
Therefore P ( 75 < (x) < 90) = ⁹⁰∫₇₅ 3/50³ ( 100 - x)² dx
= 3/50³ [ -2 (100 - x ]₇₅⁹⁰
= (3 ( -20 + 50)) / 50₃
= 9 / 12500 = 0.00072
b)
f(k) (x) = nf(x) ( ⁿ⁻¹_k₋ ₁) ( F(x) )^k-1 ; ( 1 - F(x) )^n-k
Now for n = 3, k = 2
f(2) (x) = 3f(x) × 2 × (x-50 / 50) ( 1 - (x-50 / 50))
= 6 × 1/50 × ( x-50 / 50) ( 100-x / 50)
= 6/50³ ( 150x - x² - 5000 )
therefore
P( 75 < x2 < 90 ) = 6/50³ ⁹⁰∫₇₅ ( 150x - x² - 5000 ) dx
= 99 / 250 = 0.396
Answer:
Step-by-step explanation:
To start calculating, we first need to make some proof.
Firstly, since AB = AC, we know that ΔABC is isosceles, which means that ∠ABC = ∠ACB.
Now, looking only to ΔBDE and ΔCDF, we can see that they are similar, because the two of its angles are congruent:
∠BED=∠CFD
∠DBE=∠DCF
To make it easier to visualize which are the corresponding vertexes, we can draw them like this:
And we need to remember that BC is 24, so:
BD+CD=24
Since the triangles are similar, their corresponding sides have constant ratio, which we can calculate from the corresponding sides DE and CF:
This ratio is the same for the other corresponding sides, so we can apply that for BD and CD:
Thus, the measure of CF is approximately 13, alternative D.
Answer:
The answer is 6.79 dollars
Step-by-step explanation:
The answer is 6.79 dollars because 5 times 1 (she bought 5 eggs for 1 dollar each) + the added basket 1.79 equals $6.79
