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3 years ago

How can you use a pattern to add 20+30+40+50+60+70+80

Mathematics

1 answer:

Usimov [2.4K]3 years ago

8 0

Answer:

$\displaystyle \: \: \: \: 7 \\ \: \: \sum \: (10n + 10) \\ n = 1$

Step-by-step explanation:

You can use Summation Notation as a pattern to evaluating "20 + 30 + 40 + 50 + 60 + 70 + 80":

$\displaystyle \: \: \: \: 7 \\ \: \: \sum \: (10n + 10) \\ n = 1$

I am joyous to assist you anytime.

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Mark and Don are planning to sell each other their marble collections at a garage sale. If Don has 1 more than 3 times the numbe

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Answer: Mark has 28 marbles while Don has 85 marbles.

Step-by-step explanation:

Let x represent the number of marbles that Mark has.

Let y represent the number of marbles that Don has.

If Don has 1 more than 3 times the number of marbles Mark has, it means that

y = 3x + 1

The total number of marbles is 113. It means that

x + y = 113- - - - - - - - - - - - 1

Substituting y = 3x + 1 into equation 1, it becomes

x + 3x + 1 = 113

4x + 1 = 113

4x = 113 - 1 = 112

x = 112/4

x = 28

y = 3x + 1 = 3 × 28 + 1

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3 years ago

To get on the top players list , don needs to have a minimum average score of 225 after playing four games. His scores on his fi

Black_prince [1.1K]

Average must be 225 or more
4 games so
$\frac{score1+score2+score3+score4}{4} \geq 225$
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score2=214
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score4=?
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$\frac{192+214+250+?}{4} \geq 225$
$\frac{656+?}{4} \geq 225$
times both sides by 4 to clear fraction
656+?≥900
minus 656 from both sides
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min score is 244

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3 years ago

Read 2 more answers

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DIA [1.3K]

A. or 27 is the answer

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2 years ago

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The answer is 430 :)

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3 years ago

Which number makes this sentence true? 32:40=48:x

Sav [38]

Answer:

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Step-by-step explanation:

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3 years ago

How can you use a pattern to add 20+30+40+50+60+70+80​

How can you use a pattern to add 20+30+40+50+60+70+80