Answer:
a) X ~ 
b) μ = 100/3
c) 
d) A battery is expected to last 100/3 months (33 months and 10 days approximately).
e) For seven batteries, i would expect them to last 700/3 months (approximately 19 years, 5 months and 10 days).
Step-by-step explanation:
a) The life of a battery is usually modeled with an exponential distribution X ~ 
b) The mean of X is μ = 1/0.03 = 100/3
c) The standard deviation is 
d) The expected value of the bateery life is equal to its mean, hence it is 100/3 months.
e) The expected value of 7 (independent) batteries is the sum of the expected values of each one, hence it is 7*100/3 = 700/3 months.
Answer:
To answer this question, you need to makes the unit of the smartphone screen same. In this case, phone A is using decimal and phone B is using a fraction. You can use which was easier.
Let's try to use decimal. Then you need to convert phone B fraction width into decimal width. The calculation would be: 5cm + 1/3cm= 5 cm + 0.333cm= 5.333cm
From here it clear that phone B has a wider screen than phone A.
Step-by-step explanation:
2/3 and 12/18 are equivalent fractions, and 12+18 = 30 so the answer is 12:18
Answer:
m= 9
Step-by-step explanation:
63/7