Cache access time is not given, so considering it negligible. 8 cycles / word fetch from MM. 1 cycle for sending an address to MM.
Miss rate old = 14.8% , Line size = 1word
Total cycles = (0.148)*(1 * 8 + 1) = 1.332 cycles
Miss rate new = 2.6% , Line size = 4words
Total cycles = (0.026)*(4 * 8 + 1) = 0.858 cycles
Speedup = told/tnew = 1.55
Is it right answer ?