Answer:
QT = 18
Step-by-step explanation:
The answer is 670.
this is because 96 plus 287 is 383.
so he sold 287 on the 1st day, and 383 on the second day.
383 plus 287 equals 670.
C
If we drew a line of best fit, the gradient would be roughly equal to 1, and the y intercept would be at around -4
Answer:
80.0456<
<81.1210
Step-by-step explanation:
-Given the mean,
and
, the confidence interval can be calculated using the formula:

#We substitute our values in the formula to solve for CI:
![=\bar x\pm z\times \frac{\sigma}{\sqrt{n}}\\\\=\bar y\pm z_{0.05}\times \frac{s}{\sqrt{72}}\\\\=80.5833\pm 1.645\times \frac{2.77369}{\sqrt{72}}\\\\=80.5833\pm0.5377\\\\=[80.0456,81.1210]](https://tex.z-dn.net/?f=%3D%5Cbar%20x%5Cpm%20z%5Ctimes%20%5Cfrac%7B%5Csigma%7D%7B%5Csqrt%7Bn%7D%7D%5C%5C%5C%5C%3D%5Cbar%20y%5Cpm%20z_%7B0.05%7D%5Ctimes%20%5Cfrac%7Bs%7D%7B%5Csqrt%7B72%7D%7D%5C%5C%5C%5C%3D80.5833%5Cpm%201.645%5Ctimes%20%5Cfrac%7B2.77369%7D%7B%5Csqrt%7B72%7D%7D%5C%5C%5C%5C%3D80.5833%5Cpm0.5377%5C%5C%5C%5C%3D%5B80.0456%2C81.1210%5D)
Hence, the confidence interval lies between 80.0456 and 81.1210
So... let's say the amounts invested were "a" at 6% and "b" at 7.5%.
ok.. hmm what's 6% of a? well, (6/100) * a or 0.06a.
what's 7.5% of b? well, (7.5/100) * b or 0.075b.
now... we know, whatever "a" and "b" are, they total the investment of 5000 bucks, thus
a + b = 5000and the interest yielded was 337.50, thus
0.06a + 0.075b = 337.50thus

solve for "a", to see how much was invested at 6%.
what about "b"? well, b = 5000 - a.