GMAT · Quantitativeaptitude · Probability — Spot Error

Exercise and reference answers

Questions

1. Statement parts

   1. P(A
   2. ∩
   3. B)
   4. =
   5. P(A)
   6. +
   7. P(B)
   8. always
   9. .

   Correction

   × (multiply for independent events)

   Incorrect part

   +

2. Statement parts

   1. The
   2. probability
   3. of
   4. at
   5. least
   6. one
   7. event
   8. is
   9. 1
   10. −
   11. P(none
   12. occur)
   13. always
   14. .

   Correction

   is a useful formula

   Incorrect part

   1

3. Statement parts

   1. Independent
   2. events
   3. mean
   4. P(A
   5. |
   6. B)
   7. =
   8. P(B)
   9. .

   Correction

   P(A)

   Incorrect part

   P(B)

4. Statement parts

   1. P(A
   2. ∪
   3. B)
   4. =
   5. P(A)
   6. +
   7. P(B)
   8. always
   9. .

   Correction

   only for mutually exclusive events

   Incorrect part

   always

Instructions

Tap the wrong word in each probability statement.