27-5 = 22
22/11 = 11
there are 11 boys at the party
expression = b+5
No. i*i = -1
2i*3i=-6
now if they meant complex numbers the answer is still no
(2+4i)(2-4i) = 4-8i+8i-16 = -12
Answer:
5040,56
Step-by-step explanation:
We have to construct pass words of 4 digits
a) None of the digits can be repeated
We have total digits as 0 to 9.
4 digits can be selected form these 10 in 10P4 ways (since order matters in numbers)
No of passwords = 10P4
= 
b) start with 5 and end in even digit
Here we restrain the choices by putting conditions
I digit is compulsorily 5 and hence only one way
Last digit can be any one of 0,2,4,6,8 hence 5 ways
Once first and last selected remaining 2 digits can be selected from remaining 8 digits in 8P2 ways (order counts here)
=56
#9 is answer A) yes,
#10 the answer is A) (n,j)