Jake spent a total of 70 cents.
b = black-and-white = 8 cents
c = color = 15 cents
70 = 8b + 15c
he made a total of 7 copies
b + c = 7
system of equation:
70 = 8b + 15c
b + c = 7
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b + c = 7
b + c (-c) = 7 (-c)
b = 7 - c
plug in 7 - c for b
70 = 8(7 - c) + 15c
Distribute the 8 to both 7 and - c (distributive property)
70 = 56 - 8c + 15c
Simplify like terms
70 = 56 - 8c + 15c
70 = 56 + 7c
Isolate the c, do the opposite of PEMDAS: Subtract 56 from both sides
70 (-56) = 56 (-56) + 7c
14 = 7c
divide 7 from both sides to isolate the c
14 = 7c
14/7 = 7c/7
c = 14/7
c = 2
c = 2
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Now that you know what c equals (c = 2), plug in 2 for c in one of the equations.
b + c = 7
c = 2
<em>b + (2) = 7
</em><em />Find b by isolating it. subtract 2 from both sides
b + 2 = 7
b + 2 (-2) = 7 (-2)
b = 7 - 2
b = 5
Jake made 5 black-and-white copies, and 2 color copies
hope this helps
Mean = 60 / 4 = 15
13 - 15 = -2
17 - 15 = 2
9 - 15 = -6
21 - 15 = 6
Total of squares = 4 + 4 + 36 + 36 = 80
because this is a sample we divide this by n - 1 ( = 3)
Standard deviation = sqrt (80/3) = 5.16 answer
Answer:
Step-by-step explanation:
5p + 2(p + 4) .......because pencil cases (p) sell for 5 bucks a piece....and mechanical pencils (p + 4), sell for 2 bucks a piece. She is basically selling 4 more mechanical pencils then she is pencil cases.
Answer:
In a survey of 2,300 people who owned a certain type of car, 1,610 said they would buy that type of car again. What percent of the people surveyed were satisfied with the car?
1610/2300x100=
70%
Step-by-step explanation:
total number of people for the survey= 2300
those that wanted to buy the car= 1610
percentage= 1610/2300x 100=0.7x 100
percentage= 70%
Answer:
there are 10 red marbles, 10 yellow marbles and 10 green marbles.
Step-by-step explanation:
think 1/4. the 4 is the same as 40 so if there is 1 that would be 10. so the rest of the colors are all 10 marbles:)