A phone manufacturer has 4 different types of phones namely: x1, x2, x3, and x4. if x2 costs 12% less than x1 and x3 costs 15% lesser than x2, and x4 costs 5% less than x3. what percent of x1's cost is x4?  Choose the correct choice from the following answers:
A) 89.1%  B) 77.8%  C) 60.7%  D) 80.4%  E) 71.06%
Let the cost of x1 be $100   x2 costs 12% less than x1=$100-$12--88(cost of x2)   x3 costs 15% lesser than x2--$88-13.2--74.8(cost of x3)   x4 costs 5% less than x3--74.8-3.74--71.06(cost of x4)   therefore --71.06*100/100   Answer is 71.06%
<result>E</result>
A phone manufacturer has 4 different types of phones namely: x1, x2, x3, and x4. if x2 costs 12% less than x1 and x3 costs 15% lesser than x2, and x4 costs 5% less than x3. what percent of x1's cost is x4?