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2 years ago

How many 2 digit numbers are the product of two different primes

Mathematics

2 answers:

professor190 [17]2 years ago

4 0

Answer:

30.

Step-by-step explanation:

2 digit Numbers which have factor of 2:

2*3, 2*5, 2*7, 2*11, 2*13, 2*17, 2*19, 2*23, 2*29, 2*31, 2*37, 2*41, 2*43, 2*47.

That's 14.

Then there are the ones with factor 3:

3*5 ....... 3*31 = 9 numbers.

Then

5*7 to 5*19 = 5 numbers.

7*11 , 7*13 = 2 numbers.

Total is 14 + 9 + 5 + 2

= 30.

charle [14.2K]2 years ago

3 0

Answer:

From these number, only 12,15 and 21 can be represented by a product of two one-digit number

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Answer:

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Step-by-step explanation:

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3 years ago

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3 years ago

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Harman [31]

Answer:

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b) 0.1587

c) 0.369

Step-by-step explanation:

We are given the following information in the question:

Mean, μ = 12.2 grams

Standard Deviation, σ = 2.8 grams

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Formula:

$z_{score} = \displaystyle\frac{x-\mu}{\sigma}$

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b) P(contains more than 15 grams of impurities)

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$= 1 - P(z \leq 1)$

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$P(x > 610) = 1 - 0.8413 = 0.1587 = 15.87\%$

c) P(contains between 12 and 15 grams of impurities)

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denis23 [38]

Answer:

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