self Maths Puzzle

If a, a + 2 and a + 4 are prime numbers, then the number of possible solutions for a is

Read Solution (Total 3)

there is only two solution i.e. 1 and3
11 years agoHelpfull: Yes(0) No(2)

only one solution
i.e. a=3
11 years agoHelpfull: Yes(0) No(1)
for a=1, 1,1+2,1+4 satisfies condition. for a=3, condition satisfied as well. but for other primes, condition not satisfied. so a=1 & 3.
11 years agoHelpfull: Yes(0) No(0)

self Other Question

x started a business with 10000 rupees after 4 months y joined the business with a capital of 5000 rupees. After 1 year they got a profit of 3400 , then what is x share If m and n are integers divisible by 5, which of the following is not necessarily true?
option
a) (m - n) is divisible by 5.
b) (m^2 - n^2) is divisible by 25
c) (m + n) is divisible by 10
d) None of these