the answer is in the picture above
Answer:
a + 56.75 = 76.75
Step-by-step explanation:
that is because ,money raised on first day(a) + money raised on second day = 76.75
that gives us, a = $20
Answer:
(- 2, 6 )
Step-by-step explanation:
Given the equations
3x + 2y = 6 → (1)
y - x = 6 ( multiply through by 3 to clear the fraction )
2y - 3x = 18 ( add 3x to both sides )
2y = 18 + 3x → (2)
Substitute 2y = 18 + 3x into (1)
3x + 18 + 3x = 6
6x + 18 = 6 ( subtract 18 from both sides )
6x = - 12 ( divide both sides by 6 )
x = - 2
Substitute x = - 2 into (1) and solve for y
3(- 2) + 2y = 6
- 6 + 2y = 6 ( add 6 to both sides )
2y = 12 ( divide both sides by 2 )
y = 6
solution is (- 2, 6 )
Answer: 68% of light bulbs last between 1765 hours and 1835 hours.
Step-by-step explanation:
The empirical rule states that for a normal distribution, nearly all of the data will fall within three standard deviations of the mean . The empirical rule is further illustrated below
68% of data falls within the first standard deviation from the mean.
95% fall within two standard deviations.
99.7% fall within three standard deviations.
From the information given, the mean is 1800 hours and the standard deviation is 35 hours.
1 standard deviation = 1 × 35 = 35
1800 - 35 = 1765 hours
1800 + 35 = 1835 hours
Therefore, 68% of light bulbs last between 1765 hours and 1835 hours.
Answer:
$23.31
Step-by-step explanation:
$21 x 1.11 = $23.31