Question

all possible three digit even numbers which can be formed with the condition that if 5 is one of the digits, then 7 is the next digit:
a)5
b)325
c)345
d)365

Answer 1

365 is the correct answer .....................................................

Answer 2

1) Given, 3 digit even numbers so the last digit can be 0,2,4,6,8. There are 5 possibilities.

2) The tens’ place can be any number between 0 and 9 except 5. There are 9 possibilities.

3) The hundredths place can be anything between 1 and 9 except 5 because if 5 is present then the next digit must be 7 so the numbers must be 572,574,576,578,570 which will be treated separately. So There are 8 possibilities.

So Total of 8*9*5+5=365.

Hope this helps!