Answer:
5/66
Step-by-step explanation:
x + 2x - 11 + x(x+5) + 38 = 132
x + 2x - 11 + x^2 + 5x + 38 = 132
x^2 + 8x + 27 = 132
x^2 + 8x + 27 - 132 = 0
x^ + 8x - 105 = 0
(x + 15)(x - 7) = 0
x = -15 or x = 7
But x cannot be negative, it's meant to be natural number, therefore x = 7.
N = number of stamps from the 19th century = 7 + 14 - 11 = 7 + 3 = 10
Probability that it is from 19th century = 10/132= 5/66