Question

A bag contains colored balls of which at least 90% are red. Balls are drawn from the bag one by one and their color noted. It is found that 49 of the first 50 balls drawn are red. Thereafter 7 out of every 8 balls are red. The number of balls in the bag CA

Answer 1

Answer:

Let number of balls in the bag is n.

Let, m number of times 8 balls are drawn.

Therefore, n = 50 + 8m

Red balls = 49 + 7m

Percentage of red balls = {(49 + 7m)/(50 + 8m)}*100 ≥ 90

• 49 + 7m ≥ 50*0.9 + 8m*0.9

• 49 + 7m ≥ 45 + 7.2m

• 0.2m ≤ 4

• m ≤ 20

• n ≤ 50 + 8*20 = 210

so any number greater than 210 is the answer