A two digit number less than 30 is written down at random. What is the probability that it Will be a prime number?

there are 20 2 digit numbers less than 30.

out of all of them 6 are prime

then there is only a 6/20 chance that it will be a prime number, or a 30% chance.

college

δabc ≅ δdcb by sas because

db ≅ ac . . given (side)

bc ≅ bc . . reflexive property (side)

∠dbc ≅ ∠ acb . . alternate interior angles where transversal bc crosses parallel lines bd and ac (included angle)