Flashcards-1

Some important concepts(Coutesy: Foundations of GMAT Math by Manhattan GMAT)

Number Properties

• factors

If 6 is divisible by 1,2,3 and 6 then 1,2,3 and 6 are factors of 6

• Prime numbers

Numbers divisible by 1 and itself
2 is the only even prime number
2,3,5,7,11,13,17,19 are some prime numbers

• Prime Factorization

Breaking a number into its prime factors. Eg. 60=2*2*3*5

• If 12 is divisible by 6 and 6 is divisible by 3 then 12 is divisible by 3 as well
• If x no. of apples can be spli evenly into 5 groups =>divisiblity problem
• If the number q is divisble by 9,18 and 27 then find LCM of the 3 numbers to find multiples of q