Question

Which pair of ratios does not form a true proportion?
A) 8:14 and 20:35
B) 6 to10 and 15 to 25
C) 9 5 = 27 15
D) 12:15 and 30:50

Answer 1

if a/b = c/d the ad = bc
so, check the choices.
Does 14*20 = 8*35? yes
Now find the one which fails the test