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IrinaVladis [17]
2 years ago
15

Problem 10 / (Second Session 2006)

Mathematics
1 answer:
hammer [34]2 years ago
7 0

Answer:

Find other solutions in explanation

x = 250

y = 1750

Step-by-step explanation:

x = cost per copybook

y = cost per pen

2. Sum of the cost of 4 copy books and 3 pen is equal to 7750

3.)

2x+y=2750 - - (1)

4x + 3y = 7750 - - - (2)

From (1)

y = 2750 - 2x

Substitute y = 2750 - 2x into (2)

4x + 3(2750 - 2x) = 7750

4x + 8250 - 6x = 7750

-2x = - 500

x = 500/2

x = 250

y = 2750 - 2(500)

y = 2750 - 1000

y = 1750

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Answer:

first X=8.94

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Step-by-step explanation:

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  x^2=16+64=80

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5 0
3 years ago
A bowling alley usually rents out between 22 and 25 pairs of bowling shoes during each of the 9 hours they are open. Which of th
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B

Step-by-step explanation:

22+25=47

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3 years ago
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7 0
2 years ago
Read 2 more answers
In a study published on January 31, 2011 in The Proceedings of the National Academy of Sciences, researchers randomly assigned 1
Kaylis [27]

Answer:

d.

Step-by-step explanation:

Hello!

The objective of this test is to know if aerobic exercise modifies hippocampus activity. A random sample of 120 elderly men and women was taken and divided into two groups.

Group 1: Walked around a track three times a week.

Group 2: Did a variety of less aerobic exercises, including yoga and resistance training with bands.

After a year their brains were scanned showing that group 1 had an increase of 2% in their hippocampus and group 2 showed a decrease of 1.4%

a. True, this type of observational study can be the prelude to a more formal statistical study.

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I hope it helps!

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3 years ago
HELLPPP <br> I need help asappp
sattari [20]

Answer:

(8,5)

Step-by-step explanation:

x=8

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