A box contains 21 balls numbered 1 to 21 . A ball numbered 1 to 21 . A ball is drawn and then another ball is brawn without replacement . What is the probability that both balls are even numbered?

A 2/7
B 3/14
C 8/21
D 5/21

Correct Answer: 3/14

There are 10 even number in the group 1 - 21 ∴ The probability that the first ball is even numbed 1021 And the probability that the second ball is even numbered 920 ∴ Required probability = = 1021×920 = 90420 = 314
Bissoy MCQ
#গণিত #সম্ভাব্যতা (Probability) #Combined Bank (সমন্বিত ব্যাংক) #জনতা ও রূপালী ব্যাংক- অফিসার ১৩.১২.২০১৯

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