(Original Price $425.4)
$328 × 30% = 98.4
328 + 98.4 = $426.40
I'm tentatively changing my answer to say this kind of relies on practical knowledge of how stores tend to operate. If 20 coupons are given out, the store has sold all 500 shirts, arguably at a loss to the retailer. They have to have more shirts in stock to be sold at full price because, well, that's how they make money. It's more likely that such a store would carry more than just 500 shirts at the start of each day, so A is (probably) wrong.
The answer would be 0.3635
(a) I can't help you with using your calculator for this part, but if you have some familiarity with your device you can check your answer with mine.
The mean is simply the sum of all the house costs divided by the number of houses:
(75k + 75k + 150k + 155k + 165k + 203k + 750k + 755k)/8 = 291k
So the population mean is $291,000.
The population standard deviation is the square root of the population variance. To get the variance, you take the sum of all the squared differences between the cost and the mean cost, then divide that sum by the number of houses. That is,
[(75k - 291k)² + (75k - 291k)² + … + (755k - 291k)²]/8 = 581,286k
Note that the variances is measured in square dollars. Then the standard deviation is
√(581,286k) ≈ $762,421.1
(b) The median is just the price in the middle. There were 8 houses sold, so there are 2 "middle" prices. The median is the average of these:
(155k + 165k)/2 = 160k = $160,000
(c) Yes, the mode is the data that shows up most frequently. This happens at the lower end, with $75,000 appearing twice.
So to get the fractions easier to understand you need to put them on the same level you are on. So change the 9/10 gallons to 18/20 ( this makes them easier to deal with the 1/20)
so put 1/20 into 18/20. Liam can paint 18 bird houses.
