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Here is a nice way to see and remember this. Look at the sum of the first 5 counting number Write them as 1,2,3,4,5 Now write them backward as 5,4,3,2,1 Place the second list under the first list and add the numbers in each column. Each sum is 6 and there are 5 sums. However, you counted the numbers twice since you wrote the list both ways. So the sum of the first 5 numbers is 5x6/2 In general the sum of the first n natural numbers is n(n+1)/2 So the sum of the first 100 numbers is 100x101/2=50x101=5050 This formula can also be proved by induction and several other ways.
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What code be the first number that has letter A?
Astonishingly, if you write the counting numbers in words,you don't use the letter 'A' until "one thousAnd".Note: ' 101 ' is "one hundred one", NOT "one hundred andone".
If you count from one to hundred how many 6 will you pass on the way?
The number 6 appears 20 times when counting from one to one hundred.
What is the sum of the first one hundred consecutive odd natural counting numbers?
Their sum is 10000.
What is the origin of number one?
I don't think there is such a thing.
How high would you have to count before you would use the letter A in the English language spelling of a whole number?
Unless you're counting like one hundred and one, one hundred and two, one hundred and three, one thousand is the first time you encounter the letter A.It takes 7550 letters until you hit the letter A.
What code be the first number that has letter A?
Astonishingly, if you write the counting numbers in words,you don't use the letter 'A' until "one thousAnd".Note: ' 101 ' is "one hundred one", NOT "one hundred andone".
If you count from one to hundred how many 6 will you pass on the way?
The number 6 appears 20 times when counting from one to one hundred.
What is the sum of the first one hundred consecutive odd natural counting numbers?
Their sum is 10000.
What is the origin of number one?
I don't think there is such a thing.
What is the first composite number when counting from one?
4 is the first composite number greater than 1.
How do you spell 1129?
The number is spelled out "one thousand one hundred twenty-nine" , or alternately "eleven twenty-nine" (as a time or non-counting number).
How high would you have to count before you would use the letter A in the English language spelling of a whole number?
Unless you're counting like one hundred and one, one hundred and two, one hundred and three, one thousand is the first time you encounter the letter A.It takes 7550 letters until you hit the letter A.
How many sixes are in one hundred counting from one?
20.
What was the first big number?
one hundred
Is every odd number greater then one a prime number?
No. The first odd number, counting up from one, that is not a prime number, is 9.
What is the first number to have an a in it?
This is for North Americans: Ignoring a hundred (should really be one hundred), one thousand. In UK: One hundred and one
How many zero are there in a billion?
nine - look at the last number of any number and start counting as ones. Then move left and start counting as tens, then hundreds, thousands, ten thousands, hundred thousands, millions, ten millions, hundred millions, billions, ten billions, hundred billions, trillions, ten trillions, and finally hundred trillions. So 1,000,000,000 is one billion.
