X = number of days it would take Kate to paint the house by herself. .
<span>x+5 = number of days it would take Jean to paint the house by herself.</span>
<span>Together, they paint the house in 6 days: </span>
<span>1/x + 1/(x+5) = 1/6 </span>
<span>Multiply both sides by 6x(x+5) </span>
<span>6(x+5) + 6x = x(x+5) </span>
<span>12x + 30 = x^2 + 5x </span>
<span>x^2 − 7x − 30 = 0
</span>therefore the answer is A.
To solve for the confidence interval for the population
mean mu, we can use the formula:
Confidence interval = x ± z * s / sqrt (n)
where x is the sample mean, s is the standard deviation,
and n is the sample size
At 95% confidence level, the value of z is equivalent to:
z = 1.96
Therefore substituting the given values into the
equation:
Confidence interval = 3 ± 1.96 * 5.8 / sqrt (51)
Confidence interval = 3 ± 1.59
Confidence interval = 1.41, 4.59
Therefore the population mean mu has an approximate range
or confidence interval from 1.41 kg to 4.59 kg.
A mixed number is a combination of a whole number and a fraction, so in this case we have 8 as the whole part and 0.45 as the fraction, 0.45 is equal to 45/100, and that fraction can be simplified as well, lets see:
8.45 = 8 45/100
= 8 9/20