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mars1129 [50]
2 years ago
9

a parking meter accepts only 20p coins or 50p coins.On one day, 39 coins were collected with a total value of $11.40. find how m

any 50p coins were collected.​
Mathematics
2 answers:
Snowcat [4.5K]2 years ago
6 0

Answer:

x + Y = 39 or x = 39-y

20x + 50y = 1.40

20 (39 - y) + 50y = 11.40

7.80 - 20y + 50y = 11.40

30y = 11.40 - 7.80

30y = 3.60

y = 3.60/30

y = 12 50p coins were collected.

x = 39 - 12 = 27 20p coins were collected.

Proof:

20*27 + 50*12 = 11.40

5.40 + 6 = 11.40

11.40 = 11.40

I hope it helps.

alina1380 [7]2 years ago
3 0

Answer:

  12 50p coins were collected

Step-by-step explanation:

Let x represent the number of 50p coins. Then 39-x is the number of 20p coins. The total value of coins collected was ...

  20(39-x) +50(x) = 1140

  780 +30x = 1140 . . . . . . . simplify

  30x = 360 . . . . . . . . subtract 780

  x = 12 . . . . . . . . . divide by 30

12 of the 50p coins were collected.

__

39 -12 = 27 of the 20p coins were collected.

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Answer:

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Step-by-step explanation:

you have to substitute 2 for every x you see:

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volume = 10,082.5 in³

Step-by-step explanation:

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3 years ago
A department store uses a markup of 40%. Calculate the selling price of a shirt that cost the retailer $25.
drek231 [11]
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8 0
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Customers arrive at a movie theater at the advertised movie time only to find that they have to sit through several previews and
sergij07 [2.7K]

Answer:

a) sample size is 40

Step-by-step explanation:

(a)

\sigma=4 minutes

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Keywords:

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3 0
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viktelen [127]
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Then, when it hits the ground, h(t)=0, so
0=-4.9t²+98t
98t=4.9t²
4.9t=98
t=20
☺☺☺☺
8 0
2 years ago
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