If he completes it 95% of the time. The vault she should choose is: b. vault #2, 5.13 > 2.28.
Vault to choose
Given:
Vault #1
Earning=9.1
Completion unsuccessful=75%
Vault #2
Earning=5.4
Completion successful=95%
Hence:
Vault #1=(1-75%% )x 9.1
Vault #1= 2.275
Vault #1=2.28 (Approximately)
Vault #2=95% x 5.4
Vault #2 = 5.13
Hence:
5.13 > 2.28
Therefore based on the above the vault she should choose is: b. vault #2, 5.13 > 2.28 because the vault #2 is the best choice.
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