A) 2x -3(3x -7) = 7 . . . . substitute for y
.. -7x = -14 . . . . . . . . . . . subtract 21
.. x = 2 . . . . . . . . . . . . . divide by -7
.. y = 3*2 -7 = -1 . . . . . . substitute for x
(x, y) = (2, -1)
B) 5(5x -2y) -2(3x -5y) = 5(8) -2(1) . . . . subtract 2 times 2nd equation from 5 times 1st
.. 19x = 38 . . . . simplify
.. x = 2 . . . . . . . divide by 19
.. y = (5x -8)/2 = 1 . . . . solve 1st equation for y, substitute x
(x, y) = (2, 1)
C) See the first graph.
(x, y) = (-4, 1)
D) See the second graph.
(x, y) = (3, 2)
All of these questions will be exponents and variables.
Answer:
69.14% probability that the diameter of a selected bearing is greater than 84 millimeters
Step-by-step explanation:
According to the Question,
Given That, The diameters of ball bearings are distributed normally. The mean diameter is 87 millimeters and the standard deviation is 6 millimeters. Find the probability that the diameter of a selected bearing is greater than 84 millimeters.
- In a set with mean and standard deviation, the Z score of a measure X is given by Z = (X-μ)/σ
we have μ=87 , σ=6 & X=84
- Find the probability that the diameter of a selected bearing is greater than 84 millimeters
This is 1 subtracted by the p-value of Z when X = 84.
So, Z = (84-87)/6
Z = -3/6
Z = -0.5 has a p-value of 0.30854.
⇒1 - 0.30854 = 0.69146
- 0.69146 = 69.14% probability that the diameter of a selected bearing is greater than 84 millimeters.
Note- (The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the p-value, we get the probability that the value of the measure is greater than X)
Answer:
First of all, he have to find out what 0.5% of the students is.
Second of all, find out what 0.5 of 100 is. 100 divided by 0.5 is 200.
Third of all, divide 200 from 639. This equals 3.195
Since it is asking about how many, I would go with about 3. After all, you can't have have half of a person, so the decimals shouldn't be added.
Step-by-step explanation:
Given:
Scale of the map 1 1/4cm : 8 yards
Rectangular Park: width : 2 1/2 cm ; length : 6 1/4 cm
Circular Pond: pi = 3.14 ; diameter 1 1/4 cm
Convert mixed factions into fractions.
Scale 1 1/4 = (4*1+1)/4 = 5/4
Width: 2 1/2 = (2*2+1)/2 = 5/2
Length: 6 1/4 = (4*6+1)/4 = 25/4
Diameter: 1 1/4 = (4*1+1)/4 = 5/4
width / scale * 8 yds = width in yards
5/2 ÷ 5/4 = 5/2 * 4/5 = 20/10 = 2 * 8 yds = 16 yds
length / scale * 8 yds = length in yards
25/4 ÷ 5/4 = 25/4 * 4/5 = 100/20 = 5 * 8 yds = 40 yds
Area of a rectangular park = l * w = 40 yds * 16 yds = 640 yds²
diameter / scale * 8 yds = diameter in yards
5/4 ÷ 5/4 = 5/4 * 4/5 = 20/20 = 1 * 8 yds = 8 yds.
radius = d/2 = 8/2 = 4
Area of a circular pond = πr² = 3.14 * 4² = 3.14 * 16yds² = 50.24 yds²
