Answer:
see explanation
Step-by-step explanation:
Under a reflection in the line y = x
a point (x, y ) → (y, x ) , thus
(- 1, - 2 ) → (- 2, - 1 )
(1, 1 ) → (1, 1 )
(4, - 3 ) → (- 3, 4 )
Usually when the line is going down the slope will be represented as a negative number. Remember rise/run. The slope of this line would be -2/2. If it needs to be simplified it would be -1. If answer choices are all positive best bet would be 1! Hope this helps!
Circumference of a circle - derivation
This page describes how to derive the formula for the circumference of a circle.
Recall that the definition of pi (π) is the circumference c of any circle divided by its diameter d. Put as an equation, pi is defined as
π
=
c
d
Rearranging this to solve for c we get
c
=
π
d
The diameter of a circle is twice its radius, so substituting 2r for d
c
=
2
π
r
If you know the area
Recall that the area of a circle is given by
area
=
π
r
2
Solving this for r
r
2
=
a
π
So
r
=
√
a
π
The circumference c of a circle is
c
=
2
π
r
Answer: 1¹/₈ hours
Step-by-step explanation:
Joelle spent 1¹/₂ hours reading and Rileigh spent 3/4 of that time.
To find out how much time Rileigh spent, multiply the fractions but first convert the improper fraction to a proper fraction:
= 1¹/₂ = 3/2
= 3/2 * 3/4
= 9/8
= 1¹/₈ hours
Answer:
a) 99.97%
b) 65%
Step-by-step explanation:
• 68% of data falls within 1 standard deviation from the mean - that means between μ - σ and μ + σ.
• 95% of data falls within 2 standard deviations from the mean - between μ – 2σ and μ + 2σ.
• 99.7% of data falls within 3 standard deviations from the mean - between μ - 3σ and μ + 3σ.
Mean of 98.35°F and a standard deviation of 0.64°F.
a. What is the approximate percentage of healthy adults with body temperatures within 3 standard deviations of the mean, or between 96.43°F and 100.27°F?
μ - 3σ
98.35 - 3(0.64)
= 96.43°F
μ + 3σ.
98.35 + 3(0.64)
= 100.27°F
The approximate percentage of healthy adults with body temperatures is 99.97%
b. What is the approximate percentage of healthy adults with body temperatures between 97 .71°F and 98.99°F?
within 1 standard deviation from the mean - that means between μ - σ and μ + σ.
μ - σ
98.35 - (0.64)
= 97.71°F
μ + σ.
98.35 + (0.64)
= 98.99°F
Therefore, the approximate percentage of healthy adults with body temperatures between 97.71°F and 98.99°F is 65%
