The life in hours of a battery is known to be approximately normally distributed, with standard deviation σ=1.25 hours. a random sample of 10 batteries has a mean life of x¯=40.5 hours. (a) is there evidence to support the claim that battery life exceeds 40 hours? use α=0.050. (b) what is the p-value for the test in part () what is the β-error for the test in part (a) if the true mean life is 42 hours? (d) what sample size would be required to ensure that β does not exceed 0.1 if the true mean life is 44 hours? (e) round your answers to three significant digits.

x = -3

y = -18

step-by-step explanation:

to solve by substitution, substitute one variable and solve for the other. then substitute again to find the remaining variable.

x-1/3(3x-9) = -3 since y=3x-9 substittute y.

x-1/3(3x-9)=-3

x + x +3 = -3

2x+3=-3

2x+3-3= -3-3

2x=-6

x=-3

substitute again into y=3x-9

y=3(-3)-9

y=-9-9

y=-18

umumumumum

im not sure

the solution is the point

step-by-step explanation:

we have

> equation a

> equation b

adds equation a and equation b

substitute the value of x in equation b to find the value of y

the solution is the point

a is 8.b is 10.c is 10.5. d is -.5

step-by-step explanation:

just minus the smallest number from the biggest.