Most candidates attempted this question and they performed very well.  In the (a) part, while some used the method of first principle as it was in the marking scheme, others used the compound interest formular A =  P   1+ ( -R )    n .
  100

The (b) part on geometry was also well done by the candidates <ADX = 180 – (60 + 40) = 80° (sum of <s of a<).  <ABC = 180 – 80 = 100° (opp. <s of a cyclic quad).