Answer:
a. 0.047
b. Unlikely.
Step-by-step explanation:
a. The probability of a test result being wrong for a person not using mrijuana = 8 / 170 = 0.047.
b. As the probability for a wrong result is < 0.05 we can say that the test is unlikely to be wrong.
Answer:
740
Step-by-step explanation:
The n th term of an arithmetic series is
= a₁ + (n - 1)d
where a₁ is the first term and d the common difference
Given a₃ = 7 and a₇ = (3 × 7) + 2 = 21 + 2 = 23 , then
a₁ + 2d = 7 → (1)
a₁ + 6d = 23 → (2)
Subtract (1) from (2) term by term
4d = 16 ( divide both sides by 4 )
d = 4
Substitute d = 4 into (1)
a₁ + 2(4) = 7
a₁ + 8 = 7 ( subtract 8 from both sides )
a₁ = - 1
The sum to n terms of an arithmetic series is
=
[ 2a₁ + (n - 1)d ] , thus
=
[ (2 × - 1) + (19 × 4) ]
= 10(- 2 + 76) = 10 × 74 = 740
Line BE and KE are the same length, so set the 2 equations to equal and solve for P.
7p+7 = 37-3p
Add 3 p to both sides:
10p +7 = 37
Subtract 7 from each side:
10p = 30
Divide both sides by 10:
p = 30/10
p = 3
The answer is B.
Answer:
r = - 7, r = - 5
Step-by-step explanation:
Given
r² = - 12r - 35 ( add 12r to both sides )
r² + 12r = - 35
To complete the square
add ( half the coefficient of the r- term )² to both sides
r² + 2(6)r + 36 = - 35 + 36
(r + 6)² = 1 ← take the square root of both sides )
r + 6 = ± 1 ( subtract 6 from both sides )
r = - 6 ± 1, thus
r = - 6 - 1 = - 7 or r = - 6 + 1 = - 5