19. In an office, 40 percent of the workers have at least 5 years of service, and a total of 16 workers have at least 10 years of service. If 90 percent of the workers have fewer than 10 years of service, how many of the workers have at least 5 but fewer than 10 years of service?

(A) 48
(B) 64
(C) 50
(D) 144
(E) 160

Total workers = x
Workers with at least 5 years work ex = 4x/10=.4x
Workers with more than 10 years ex = 16 (which is 10% of total)
16 = .1x
Thus x = 160
Workers with at least 5 yrs ex = 160 *(40/100) = 64
Out of these 16 are with 10 yrs or more of work ex
hence workers with atleast 5 yrs of ex but less than 10 yrs of ex = 64-16=48