Question

A telephone number consists of a sequence of seven digits not starting with a 0 or a 1. How many phone numbers begin with either 7342, 7423, or 7224?
a. 27,000 numbers
b. 2,187 numbers
c. 1,000 numbers
d. 90 numbers
e. 3,000 numbers

Answer 1

7 number
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u can make 8×10^6 phone numbers