Perpetuities

in Question 7 , the teacher give second said that $ 5 k receivable in first time 3 years and totally 12 year … why the teacher count to 14 ? according to Q 7 , in this first time is 3 year , second time is 9 years so we calulate from 10 ,11, 12 , 13 , 14 , 15 , 18, 20, 21 ,22,23,24…. so will be 1 to 24 … but the teacher calculation is 1 to 14 ? why then how to count …

Thanks for your reply