SOLUTION: Numbers are formed using the digits 4,5,6,7 and 8 with no digit being used more than once. How many odd number are less than 700?
I got the answer as 15 but was told the answer
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-> SOLUTION: Numbers are formed using the digits 4,5,6,7 and 8 with no digit being used more than once. How many odd number are less than 700?
I got the answer as 15 but was told the answer
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Question 1135440: Numbers are formed using the digits 4,5,6,7 and 8 with no digit being used more than once. How many odd number are less than 700?
I got the answer as 15 but was told the answer is 25. This is my working
First digit is an even number which is either 4 or 6 and last digit is either 5 or 7
thus possible combination is 2*3(ie remaining numbers)*2(ie. possible combination of last digit) = 12
First digit is an odd number ie 5 and last digit is just 7 therefore
possible combination is 1*3*1 = 3
Therefore the answer is 12+3 = 15 possible ways. Is this correct? Thanks
The question asks for the number of odd numbers you can make that are less than 700, using the given digits. You found and counted only the 3-digit numbers that satisfy the requirements; the problem didn't specify 3-digit numbers.
5 is an example of a 1-digit number that is odd and less than 700; 67 is an example of a 2-digit number that is less than 700.
And there are more... making 25 the total number of odd numbers that are less than 700 and use only the given digits.