Both have "4 threads" but the i5 has 4 real cores while the i3 only has 2 cores.
Also consider that the i5 might have a higher clock speed and more l3 cache. Hyperthreaded cores are not faster than real cores.
The question is kind of silly, one might think that both chips would perform the same.. not think the i3 is faster. Both have 4 threads, if hyper threading was capable of delivering 100% more performance per core, then they would be very close in performance and an i7 would be twice as fast as an i5, which is NOT the case.