# When did phone numbers become more than four digits?

Those who remember the telephone party line system might remember when you could dial four digits to call someone. The four-number system was gradually phased out in the 1950s. Sometime around 1958...
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http://www.answerbag.com/q_view/2284727

## How to Find Sums of Digits?

The sum of digits, also termed arithmetically as digit sum, is simply a sum of all the digits constituting a number. The only catch is that if the sum of digits constituting a number is a number th...
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http://www.ehow.com/how_8383466_sums-digits.html

## How many threes are there in the first one million digits of pi?

The ratio of the circumference of a circle to its diameter is represented by pi. This number is an infinite decimal with no known repeating strings of numbers. The number three appears 100,230 time...
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http://www.answerbag.com/q_view/1984379

## How to Divide Double Digits?

Dividing double digits is very similar to long division with a single-digit divisor, but it does require some extra multiplication and thinking.

http://www.wikihow.com/Divide-Double-Digits

## How many digits are in a us phone numer?

Our phone numbers have 3 for the area code, 3 for the local office code and 4 unique digits for that one line. As said, ten total. If you are calling from outside of the US, you will need extra dig...
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http://answers.yahoo.com/question/index?qid=20130416115858AAlluhs