Total cycles before improvement=0.5*2+0.5(0.7(15)+0.3(200))=36.25
After improvement ,total cycles needed for memory=(100-15)% * 200=170 .
Total cycles after improvement=0.5*2+0.5(0.7(15)+0.3(170))=31.75.
Therefore, improvement or speedup=36.25/31.75=1.14