Question

how to tell if 12:17 and 10:15 are equivalent

Answer 1

12:17 and 10:15 can be rewritten as 12/17 and 10/15. We need to make the denominators similar so we find the LCM of 17 and 15 which is 255.

12/17 = 180/255
10/15 = 170/255

180$\neq$170

They are not equivalent. Hope this helps!