So, if a long distance call costs 21 cents we just use a formula first we do 20 - 9.92, which gives us 10.08, then we divide it like this: 10.08 / 0.21, which gives 48! So, Lashonda spent 48 minutes making a long distance call! Hope this helped! Brainliest is always appreciated.
The diagonal of a square is equal to the side x times square root of 2, xSqrt(2)
z = xSqrt(2), its rate of change is just Sqrt(2)
3 is multiplying by itself 7 times. The answer is 3 superscript 7.
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.