25 = -16t^2 + 50t + 4
16t^2 - 50t + 21 = 0
16t^2 - 8t - 42t + 21 = 0
8t(2t - 1) - 21(2t - 1) = 0
(8t - 21)(2t - 1) = 0
8t - 21 = 0 or 2t - 1 = 0
t = 21/8 or t = 1/2
t = 2.625 or t = 0.5
Answer:
the probability is 0.0202
Step-by-step explanation:
The computation is shown below:
Given that
The Average life span = 17 hours
Standard deviation = 0.8 hours
Sample = 30 batteries
Sample mean = 16.7 hours
Now based on the above information
The probability is

Hence, the probability is 0.0202
Subtract
1/2x = 6
Divide/multiply
x = 12
Answer:
15 360 people in State A and 58 560 in State B
Step-by-step explanation:
We have two conditions:
(1) A + B = 73 920
(2) B = 3A + 12 480
Solve the system of equations. Substitute (2) into (1).
A + 3A + 12 480 = 73 920 Subtract 12 480 from each side
4A = 61 440
(3) A = 15 360 Substitute (3) into (2)
B = 3×15 360 + 12 480
= 46 080 + 12 480
= 58 560
There are 15 360 people in State A and 58 560 in State B.
<em>Check:
</em>
(1) 15 360 + 58 560 = 73 920 (2) 58 560 = 3×15 360 + 12 480
73 920 = 73 920 58 560 = 46 080 + 12 480
58 560 = 58 560