60 because 2:4 is 1/2, and when you divide by a fraction, you multiply by the reciprocal (2/1 instead of 1/2) which would be 60 in this case.
Yes they are both equivalents because they are whole's and some examples would be 8/8,9/9,4/4. and 5/5 because they are all whole's 7 out of 7 pieces of pizza is the whole pizza.
