In Sharon Springs, Kansas, all of the phone numbers begin 852-4. The only differences in the phone numbers are the last 3 digits. How many possible phone numbers can be assigned using this system?
Many large cities have run out of phone numbers and so a new area code must be introduced. How many different phone numbers are there in a single area code if the first digit cannot be zero?
How many different phone numbers are possible using a 3-digit area code and a 7-digit phone number if the first digit of the area code and phone number cannot be zero?
A shipping service offers to send packages by ground delivery using 2 different companies, by next day air using 3 different companies, and by 2-day air using 3 different companies. How many different shipping options does the company offer?
Many large cities have run out of phone numbers and so a new area code must be introduced. How many different phone numbers are there in a single area code if the first digit cannot be zero?
How many different phone numbers are possible using a 3-digit area code and a 7-digit phone number if the first digit of the area code and phone number cannot be zero?
A shipping service offers to send packages by ground delivery using 2 different companies, by next day air using 3 different companies, and by 2-day air using 3 different companies. How many different shipping options does the company offer?
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In Sharon Springs, Kansas, all of the phone numbers begin 852-4. The only differences in the phone numbers are the last 3 digits. How many possible phone numbers can be assigned using this system?
10 * 10 * 10 = 1000
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Many large cities have run out of phone numbers and so a new area code must be introduced. How many different phone numbers are there in a single area code if the first digit cannot be zero?
(area code) _ _ _ - _ _ _ _
First digit cannot be zero (must be 1-9)
All other digits can be 0-9
9 * 10 * 10 * 10 * 10 * 10 * 10 = 9,000,000
==============================
How many different phone numbers are possible using a 3-digit area code and a 7-digit phone number if the first digit of the area code and phone number cannot be zero?
_ _ _ - _ _ _ - _ _ _ _
^ ........ ^ : Digits 1 through 9
All others: Digits 0 through 9
9 * 10 * 10 * 9 * 10 * 10 * 10 * 10 * 10 * 10 = 8,100,000,000
==============================
A shipping service offers to send packages by ground delivery using 2 different companies, by next day air using 3 different companies, and by 2-day air using 3 different companies. How many different shipping options does the company offer?
Since all methods of delivery are independent, just add them (i.e. you will NOT be using ground delivery AND 2-day air delivery, or next day air delivery AND 2-day air delivery).
2 + 3 + 3 = 8
10 * 10 * 10 = 1000
==============================
Many large cities have run out of phone numbers and so a new area code must be introduced. How many different phone numbers are there in a single area code if the first digit cannot be zero?
(area code) _ _ _ - _ _ _ _
First digit cannot be zero (must be 1-9)
All other digits can be 0-9
9 * 10 * 10 * 10 * 10 * 10 * 10 = 9,000,000
==============================
How many different phone numbers are possible using a 3-digit area code and a 7-digit phone number if the first digit of the area code and phone number cannot be zero?
_ _ _ - _ _ _ - _ _ _ _
^ ........ ^ : Digits 1 through 9
All others: Digits 0 through 9
9 * 10 * 10 * 9 * 10 * 10 * 10 * 10 * 10 * 10 = 8,100,000,000
==============================
A shipping service offers to send packages by ground delivery using 2 different companies, by next day air using 3 different companies, and by 2-day air using 3 different companies. How many different shipping options does the company offer?
Since all methods of delivery are independent, just add them (i.e. you will NOT be using ground delivery AND 2-day air delivery, or next day air delivery AND 2-day air delivery).
2 + 3 + 3 = 8