Answer: a) (1008.34,1019.658) b) (1009.24,1018.76)
Step-by-step explanation:
Since we have given that
n = 75
mean = 1014 hours
Standard deviation = 25 hours
At 95% two sided , z = 1.96
So, confidence interval would be

(b) Construct a 95% lower confidence bound on the mean life.
z = 1.65
So, confidence interval would be

Hence, a) (1008.34,1019.658) b) (1009.24,1018.76)
Answer:
Cost for skii: J(x) = 30x + 7
Cost for beach chair: B(x) = 5x + 3
=> Total cost = J(x) + B(x) = 30x + 7 + 5x + 3 = 35x + 10
=> Option C is correct.
Hope this helps!
:)
The peaches cost more per pound because if you divide the pounds of peaches by the cost, it's more than the cost per pound of apples.
Christopher purchased 2.8 pounds of almonds and 3.5 pounds to roasted pistachios.
Step-by-step explanation:
Cost of almonds per pound = $10
Cost of roasted pistachios = $12
Total amount spent = $70
Weight of nuts = 6.3
Let,
Weight of almonds = x
Weight of roasted pistachios = y
According to given statement;
x+y=6.3 Eqn 1
10x+12y=70 Eqn 2
Multiplying Eqn 1 by 10

Subtracting Eqn 3 from Eqn 2;

Dividing both sides by 2

Putting y=3.5 in Eqn 1

Christopher purchased 2.8 pounds of almonds and 3.5 pounds to roasted pistachios.
Keywords: linear equations, elimination method
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