Answer:
119.2
Step-by-step explanation:
Given the following :
Mean (m) = 100 years
Standard deviation (sd) = 15 years
closest to the age of a Galápagos Islands giant tortoise at the 90th percentile of the
distribution?
Obtain the Zscore for 90th percentile (0.90) on the z table = 1.28
Zscore = (X - mean) / standard deviation
1.28 = (X - 100) / 15
1.28 × 15 = X - 100
19.2 = X - 100
19.2 + 100 = X
X = 119.2
I have no idea I’m answering this because I need to ask more questions
Answer:

Step-by-step explanation:

Sorry it took so long
Answer:
Solution
verified
Verified by Toppr
m
2
−3m−1=0
m
2
−3m=1 → (1)
Third term =(
2
1
coeeficientofm)
2
(
2
1
×(−3))
2
=(
2
−3
)
2
=
4
9
Adding
4
9
to both sides of equation (1), we get
m
2
−3m+
4
9
=1+
4
9
∴ m
2
−3m+
4
9
=
4
4+9
∴ (m−
2
3
)
2
=
4
13
Taking square roots on both sides
∴ m−
2
3
=±
2
13
∴ m=
2
3
+
2
13
or m=
2
3
−
2
13
m=
2
3+
13
,
2
3−
13
are the roots of the given quadratic equation.