Answer:
131/1000
Step-by-step explanation:
This is the simplest form as a fraction
131/100 is the fraction in the simplest form
a
k = 11
k/90 - 1/9 = 1/90
k/90 = 1/90 + 1/9
k/90 = 1 + 10/90
k/90 = 11/90
k = 11/90 / 90
k = 11/90 * 90