Answer:
Between 21 years and 75 years
Step-by-step explanation:
Given that a real estate company is interested in the ages of home buyers. They examined the ages of thousands of home buyers and found that the mean age was 48 years old, with a standard deviation of 9 years.
X the ages of home buyers is N(48, 9)
a)
Hence using Cheby chev inequality
b)
c) Using normal distribution we have
d) z value is 2.97
Hence x lies between
Between 21 years and 75 years
Answer:
The distance between them after 30 minutes is 6.5 km.
Step-by-step explanation:
Speed =
Sarah's speed = 6 km/hr = 1.6667 m/s
Emily's speed = 10 km/hr = 2.7778 m/s
The measure of angle between their bearings =
After 30 minutes (1800 seconds);
distance = speed x time
Sarah would have covered a distance = 1.6667 x 1800
= 3000 m
= 3 km
Emily would have covered a distance = 2.7778 x 1800
= 5000 m
= 5 km
The distance between them, a, can be determined by applying the cosine rule;
=
+
- 2bcCos A
= +
-2(5000 x 3000) Cos 105
= +
-2(5000 x 3000) x (-0.2588)
= 2.5 x + 9 x
+ 7764000
= 41764000
a =
= 6462.5073
a = 6462.5 m
The distance between them after 30 minutes is 6.5 km.