Answer:
2.7
Step-by-step explanation:
322/7=46
46*125=2.71739
round off
2.7
This cannot be fit into a normal distribution. While the first 7 runners all have times relatively close, the time of the last runner is an outlier, as it is too far from the other data points. The standard deviation is calculated by taking the mean, subtracting each value from the mean, squaring the deviations, adding these, then dividing by the number of data points (7), and taking the square root. This gives an answer of SD = 0.1107.
Number of pounds of macadamia nuts is 8 pounds and number of pounds of almonds is 4 pounds.
<u>Step-by-step explanation:</u>
Step 1:
Given total pounds of mixture = 12 pounds, cost of macadamia nuts per pound = $9, cost of almonds per pound = $5.25, total cost of mixture per pound = $7.75.
Let number of pounds of macadamia nuts be x and number of pounds of almonds be 12-x.
Step 2:
Form an equation using the above information.
⇒ 9x + 5.25 (12-x) = 12 × 7.75
⇒ 9x + 63 - 5.25x = 93
⇒ 9x - 5.25x = 30
⇒ 3.75x = 30
⇒ x = 8
Number of macadamia nuts is 8 pounds.
Step 3:
Calculate number pounds of almonds
⇒ Number of pounds of almonds = 12 - x = 4 pounds.
<h2>
Explanation:</h2>
In every rectangle, the two diagonals have the same length. If a quadrilateral's diagonals have the same length, that doesn't mean it has to be a rectangle, but if a parallelogram's diagonals have the same length, then it's definitely a rectangle.
So first of all, let's prove this is a parallelogram. The basic definition of a parallelogram is that it is a quadrilateral where both pairs of opposite sides are parallel.
So let's name the vertices as:

First pair of opposite sides:
<u>Slope:</u>

Second pair of opposite sides:
<u>Slope:</u>

So in fact this is a parallelogram. The other thing we need to prove is that the diagonals measure the same. Using distance formula:

So the diagonals measure the same, therefore this is a rectangle.
9x^2 + 18x + 9 = 5
9(x^2 + 2x +1) - 5 = 0
x^2 + 2x - 4 = 0
Then use the quadratic formula.