How many lines of symmetry does this shape have

1.5x - (x + 3) = 1/3 (9x + 18) - 5

Marysya12 [62]

Answer:

x = -1.6

Step-by-step explanation:

.5x - 3 = 3x + 6 - 5

.5x - 3 = 3x +1

-2.5x = 4

x = -1.6

7 0

3 years ago

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Michael has a drawer with 8 pairs of black socks and 12 pairs of white socks. Without looking he takes a white pair of socks out

Lesechka [4]

D because there are more pair of white socks than black socks

5 0

3 years ago

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Heart beats 2400 times during 20 minutes of running. While resting you record your heart beating 17 times in 15 seconds. What is

Mnenie [13.5K]

Answer:

1,360 beats when she is resting

Step-by-step explanation:

17 times per 15 seconds in a 20 minute span

how many 15 seconds are in 60 seconds.

There is 4 periods of 15 minutes in one minute

17 * 4 = 68

68 * 20 = 1360

I think that is correct

6 0

3 years ago

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Lisa started to drive from Boston to Washington, DC, which is 440 miles away, at 8:00 AM. For the first four hours of her trip,

sukhopar [10]

Answer:

60 mph

Step-by-step explanation:

Given;

Total distance covered d = 440 miles

Average speed in the first 4 hours v1 = 50 mph

Total time taken for the whole trip t = 8:00 to 4:00pm

t = 16:00-8:00 = 8 hours

Firstly we need to calculate the distance covered during the first 4 hours;

d1 = average speed × time = v1 × t1

t1 = 4

d1 = 50 × 4 = 200 miles

Then we need to calculate the distance covered in the second period of the journey;

d = d1 + d2

d2 = d - d1

Substituting the values;

d2 = 440 - 200

d2 = 240 miles

The time taken for the second period of travel t2;

t2 = t -t1 = 8-4

t2 = 4 hours

Average speed = distance travelled ÷ time taken

The average speed for the second part of the trip v2 is;

v2 = d2 ÷ t2

Substituting t2 and d2;

v2 = 240 miles ÷ 4 hours

v2 = 60 mph

The average speed during the second part of the trip is 60 mph

3 0

3 years ago

An article on polygraph testing of FBI agents indicated that the probability of a false-positive (a trustworthy person who nonet

Alexandra [31]

Answer:

The variable x will follow a geometric distribution, with mean = 3 and standard deviation = 3.46.

The values for P(x) are:

$P(0)=0.25\\\\P(1)=0.1875\\\\P(2)=0.1406\\\\P(3)=0.1055\\\\P(4)=0.0791\\\\P(5)=0.0593\\\\P(6)=0.0445\\\\P(7)=0.0334\\\\P(8)=0.025\\\\P(9)=0.0188\\\\P(10)=0.0141\\\\$

Step-by-step explanation:

This kind of random variables can be descripted by the geometrical distribution.

This distribution shows the probability of having an amount of "failures" before the first "success" (or the other way).

Let x be the number of trustworthy FBI agents tested until someone fails the test. The probability of failing a test is p=0.25

Then, the probability of x is:

$P(x)=q^x\cdot p$

The values for the first x are:

$P(0)=0.75^0\cdot 0.25=0.25\\\\P(1)=0.75^1\cdot 0.25=0.1875\\\\P(2)=0.75^2\cdot 0.25=0.1406\\\\P(3)=0.75^3\cdot 0.25=0.1055\\\\P(4)=0.75^4\cdot 0.25=0.0791\\\\P(5)=0.75^5\cdot 0.25=0.0593\\\\P(6)=0.75^6\cdot 0.25=0.0445\\\\P(7)=0.75^7\cdot 0.25=0.0334\\\\P(8)=0.75^8\cdot 0.25=0.025\\\\P(9)=0.75^9\cdot 0.25=0.0188\\\\P(10)=0.75^{10}\cdot 0.25=0.0141\\\\$

This probability will be descending as the the variable x increases.

The mean is:

$\mu=\frac{1-p}{p}= \frac{1-0.25}{0.25}=\frac{0.75}{0.25}=3$

The standard deviation is:

$\sigma=\sqrt{\frac{1-p}{p^2}} =\sqrt{ \frac{0.75}{0.25^2} }=\sqrt{12}= 3.46$

5 0

3 years ago