How many different factors does the integer n have?
(1) n = (a^4)(b^3), where a and b are different positive prime numbers.
(2) The only positive prime numbers that are factors of n are 5 and 7.
don't know where to begin..
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Different factors of an integer
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Hi everyone, i am new to this forum and i have a DS question...
How many different factors does the integer n have?
(1) n = (a^4)(b^3), where a and b are different positive prime numbers.
(2) The only positive prime numbers that are factors of n are 5 and 7.
don't know where to begin..
How many different factors does the integer n have?
(1) n = (a^4)(b^3), where a and b are different positive prime numbers.
(2) The only positive prime numbers that are factors of n are 5 and 7.
don't know where to begin..
IMO A
prime numbers have only itself and 1 as factors, so there are a finite number of solutions regarding the first statement...plug in examples
a=2 b =3
(2^3)(3^4)=(8)(81)
8's factors=(1,8,2,4)
81=(1,81,3,27,9)
try 5^3 and 3^4=(125)(81)
125 - 1,125,5,25
81=1,81,3,27,9
statement 2 is insufficient because the variable can include non-prime numbers as well
prime numbers have only itself and 1 as factors, so there are a finite number of solutions regarding the first statement...plug in examples
a=2 b =3
(2^3)(3^4)=(8)(81)
8's factors=(1,8,2,4)
81=(1,81,3,27,9)
try 5^3 and 3^4=(125)(81)
125 - 1,125,5,25
81=1,81,3,27,9
statement 2 is insufficient because the variable can include non-prime numbers as well
