Bunuel
In a village of 2,500 people, 800 people are over 70 years old and 850 people are female. It is known that 40 percent of the females are younger than 70 years old. If no one in the village is 70 years old, what is the probability that a person chosen at random is either a male or younger than 70 years old?
A. 221/250
B. 199/250
C. 33/50
D. 8/25
E. 51/250
2500 people
800 over 70
850 female
40% female younger than 70 = 850(0.4) = 340
850 - 340 = 510 greater than 70 for female
Males = 2500 - 850 = 1650
If 800 are greater than 70 and 510 females are greater than 70, then 800 - 510 = 290 males are greater than 70 years old.
1650 - 290 = 1360 males younger than 70
probability that a person chosen at random is either a male or younger than 70 years old:
(total males, which includes less than 70 years + females less than 70) = 1650 + 340 = 1990
1990/2500 = 199/250
Bor (males less than 70 + females less than 70 + males over 70) = 1360+340+290 = 1990
1990/2500 = 199/250
B