factor the 2 denominators:-
a^2 - 6a + 9 = (a - 3)(a - 3)
a^2 - 8a + 15 = (a - 3)(a - 5)
((a - 3) is common to both sets of factors so the LCD is:-
(a - 3)(a - 3)(a - 5) or this can be written as (a -3)^2(a - 5)
b) at least 75 papers will be missing the name
c) at most 45 papers will be missing the name
d) exactly 65 papers will be missing the name
17.27 square centimeters
193.42 square centimeters
386.85 square centimeters