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05 Why is Penicillin so important?

More documents like this are at:  chemistry in society

22-Sep-08

Before Penicillin and other antibiotics like Penicillin, people used to die sometimes just from simple cuts as the cuts get infected from bacteria.

antibiotics today save thousands of people every year.

04 How did Penicillin come to be disovered?

More documents like this are at:  chemistry in society

22-Sep-08

There was a scientist experimenting with growing bacteria in petridishes. He noticed that when there is mold, the mold killed bacteria. The chemical study of this mold yielded or gave Penicillin.

02 What is Penicilin?

More documents like this are at:  chemistry in society

22-Sep-08

Penicillin is a medicine that kills bacteria and helps with infections. Medicines like Penicillin are called antibiotics. Bacteria is responsible for some kinds of infections. Bacteria can enter body through cuts or through physical contact.

mixed fractions

More documents like this are at:  Fractions

20-Sep-08

mixed fractions

multiply fractions

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20-Sep-08

multiply fractions

Add fractions

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20-Sep-08

Add fractions

Compare fractions

More documents like this are at:  Fractions

20-Sep-08

Compare fractions

Expand fractions

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20-Sep-08

Expand fractions

Reduce fractions

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20-Sep-08

Reduce fractions

Everyday Math Made E-Z by Pete Reinert

More documents like this are at:  Math Books

20-Sep-08

simple strategies for elementary math and work problems

04 is 14 an even number?

More documents like this are at:  numbers

20-Sep-08

Yes. Because the "even" half of 14 is 7

06 is 240 an even number?

More documents like this are at:  numbers

20-Sep-08

Yes, because half of 240 is 120. So it is even.

08 is 256 an even number?

More documents like this are at:  numbers

20-Sep-08

Yes. Because 256 ends in a 6 which is a clue that says 256 can be broken down into two equal parts. In this case half of 256 happens to be 

1/2 of 200 = 100
1/2 of 50  =  25
1/3 of 6   =   3

so adding those all together you can get the half of 256 

1/2 of 256 = 128

10 What is the meaning of "even"?

More documents like this are at:  numbers

20-Sep-08

The word "even" means being equal or being fair of judgement. So an even number means the number could be evenly divided or "equally" divided into 2 equal parts. When it is not even then it is "odd".

12 when is a balance even?

More documents like this are at:  numbers

20-Sep-08

A balance is what you use to measure or compare the weight or mass of 2 things. It has 2 sides. If one of the sides is not equal to the other the balance will tilt towards the heavier one. Then the balance is said to be "uneven"

When the both sides of a balance are of "same" or "equal" weight then the balance is said to be "even".

14 is number 7 even?

More documents like this are at:  numbers

20-Sep-08

7 is not even because you can not break it into 2 equal parts

16 can you brake 7 into 2 parts?

More documents like this are at:  numbers

20-Sep-08

This is a trick question. Yes. you can break 7 into 2 parts. 3 and 4. 1 and 6. 2 and 5.

18 Can you brake 7 into 2 equal parts?

More documents like this are at:  numbers

20-Sep-08

No.

20 How do you know a number is even?

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20-Sep-08

You know a numbr is even when you are able to break it down into two equal parts.

You know a number is even when you are able ot half it with nothing remaining.

You know a number is even when it is divisible by 2.

You know a number is even if it ends in 0, 2, 4, 6, or 8.

46 what are 3 and 7 to 21?

More documents like this are at:  numbers

20-Sep-08

3 and 7 are factors for 21. And conversely 21 is a multiple of both 7 and 3. So if you count by 7s you will reach 21. You can also reach 21 if you count by 3s.

22 is 7 divisible by 2?

More documents like this are at:  numbers

20-Sep-08

7 is not divisible by 2 evenly. If you divide 7 by 2 you will have a reminder of 1.

24 is 24 divisible by 2?

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20-Sep-08

Yes. Because half of 24 is 12. So 2 goes 12 times into 24. Or 2 divides 24 leaving a quotient of 12 with a remainder of 0.

26 is 30 divisible by 2?

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20-Sep-08

30 is divisible by 2 because half of 30 is 15.

28 How do you know a number is divisible by 2?

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20-Sep-08

The rules of thumb are 

If the number ends in a zero
if the number ends in a 2, 4, 6, or 8

when that happens that number becomes divisible by 2.

30 Can you divide or break 15 in to equal parts?

More documents like this are at:  numbers

20-Sep-08

I can not break 15 into 2 equal parts but I can definitely break it down into 3 equal parts of 5 each. I know this because 3 and 5 are factors for 15 and both divides 15 with out a reminder or so to say "evenly".

32 can you break 7 into equal parts?

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20-Sep-08

No. 7 has no factors. There is no way to break 7 into equal parts.

34 can you break 11 into equal parts?

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20-Sep-08

There is no way to break 11 into equal parts. we know this because there are no factors for 11.

36 can you break 27 into equal parts?

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20-Sep-08

I can not break 27 down into "two" equal parts but I can definitely break 27 into 3 equal parts of 9 each. Because 3 and 9 are factors for 27 because 3 x 9 = 27.

38 can you break 21 into equal parts

More documents like this are at:  numbers

20-Sep-08

I can not break 21 down into "two" equal parts but I can definitely break 21 into 3 equal parts of 7 each. Because 3 and 7 are factors for 21 because 3 x 7 = 21.

40 How do you define a prime number?

More documents like this are at:  numbers

20-Sep-08

A prime number is generally defined as a number for which the only factors are 1 and the number itself.

This means the number has no other factors other than 1 and itself. So such a number can not be broken down into equal parts or grouped into equal parts.

These numbers seem to stand by themselves subservient to none or dependent on none perhaps meriting their moniker.