Question

If Jorge (were) just 15 months older, he would have finished school and be on his way to California at last
is it was or were

Answer 1

was. they both seem like they'd work, but was seems better to me

Answer 2

~Were~
because assuming that the word months is plural, and that the word 'were' was referring to 'months', our answer would have to be the plural form. Since 'was' is not plural and 'were' is, I believe this is grammatically correct.

Answer 3

I agree with @RoyalArab♥ it is "were"

Answer 4

i think "were" is a better option cause of the word "months"