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3 years ago

Katie has a collection of nickels, dimes and quarters with a total value of

Mathematics

1 answer:

garik1379 [7]3 years ago

5 0

10d+ 25q+5n= 805

D= n+8

Q= n+ 5

10d+ 25q+5n= 805

10(n+8)+25(n+5)+5n=805

10n+80+25n+125+5n=805

40n+205=805

40n=805-205

40n= 600

N=600/40

N= 15

D= n+8

D= 15+8

D= 23

Q=n+5

Q=15+5

Q=20

So 15 nickels ,23 dimes and 20quarters .

To check

15(0.05)= $0.75

23(0.10)=$2.30

20(0.25)=$5.00

Add it

5.00+2.30+0.75=8.05

7.30+.75=8.05

8.05=8.05

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7. In a state lottery, a player must choose 8 of the numbers from 1 to 40. The lottery commission then performs an experiment th

Vlad1618 [11]

Answer:a) P(8 of the players numbers are drawn)=1.3×10^-8

b) P(7 of the players number are drrawn)=3.33×10^-c) P(at least 6 of the players number were drawn)=1.84×10^-4

Step-by-step explanation:

Players has 8 combinations of numbers from 1-40. The outcome S contains all the combinations of 8 out of 40

a) P(8 of the players numbers are drawn)= 1/40/8= 1.3×10^-8

There are one in hundred million chances that the draw numbers are precisely the chosen ones.

b) Number of ways of drawing 78 selected numbers from 1-40=8×(40-7)

8×32

P(7 of the players number are drawn)=8×32/40 =3.33×10^-6.

There are approximately 300,000 chances that 7 of the players numbers are chosen

c) P(at least 6 players numbers are drawn)= 32/2×(8/6) ways to draw.

P(at least 6 players numbers are drawn)=P(all 8 chosen are drawn)+P(7 players numbers drawn)+P(6 chosen are drawn) = 1+ 8 x32/40/8 +[8\6 ×32/2]

P(at least 6 players numbers are drawn) = 1.84×10^-4.

There are approximately 5400chances that at least6 of the numbers drawn are chosen by the player.

5 0

3 years ago

How do you use long devision for -7/8? Plz help

Viktor [21]

Answer:

-0.875

Step-by-step explanation:

7 0

2 years ago

In the figure, j || k and m<1 = 63º.

Aleonysh [2.5K]

Answer: m<4 = 117 degrees

Step-by-step explanation:

Knowing that angle 1 is 63 degrees, we can look at the other angle on the same side of the line, angle 4.

Angles on one side of a line add to 180 degrees.

180 - 63 = 117

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2 years ago

A submarine descends at a rate of 60 feet per minute. How long will it take to descend to a depth of 900 feet. ?

gregori [183]

$Formula\ for\ veolocity:\\\\
velocity=\frac{distance}{time}\\
v=60\frac{feet}{min}\\
distance=900feet\\\\
velocity*time=distance\ \ |Divide\ by\ velocity\\
time=\frac{distance}{velocity}\\
time=\frac{900}{60}=15minute\\\\
\textbf{It\ will\ take\ 15\ minutes.}$

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3 years ago

John drove to Daytona Beach, Florida, in hours. When he returned, there was less traffic, and the trip took only hours. If John

olga55 [171]

Question: John drove to a distant city in 5 hours.

When he returned, there was less traffic and the trip took only 3 hours.

If John averaged 26 mph faster on the return trip, how fast did he drive each way

Answer:

For the first trip he drove at a speed of 39 mph

For the second trip he drove at a speed of 65 mph

Step-by-step explanation:

Let the distance for both journey be Z because they are equal.

Let the speed for the first journey be X

Let the speed of the second journey be Y

Formula for speed = distance ÷ time

For the first journey the speed X = Z ÷ 5

For the second journey the speed Y = Z ÷ 3

Since John averaged 26 mph faster in the second trip than the first trip due to traffic, it means that the difference in speed between the first & second trip is 26 mph

Difference in speed = (Z÷3) - (Z÷5) = 26

subtracting both results to (5Z-3Z) ÷ 15 = 26

Upon cross multiplication

2Z = 390

Z = 390÷2 = 195 miles

Therefore speed for first journey = 195 ÷ 5 = 39 mph

Speed for second journey = 195 ÷ 3 = 65 mph

To verify, 65 - 39 = 26 mph

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3 years ago