Statisticsmedium · Past Paper
A box contains 90 discs numbered 1 to 90. If one disc is drawn, what is the probability that it bears a two-digit number?
A81/90
B9/90
C10/90
D80/90
✓ Correct Answer: A — 81/90
One-digit numbers are 1 to 9 (9 numbers). Two-digit numbers = 90 - 9 = 81. 81/90 = 9/10.
Share this question
More from Statistics
- The median of a set of 10 observations is the average of which two terms when arranged in order?
- Calculate the Upper Quartile (Q3) for the following data: 10, 15, 20, 25, 30, 35, 40.
- A and B are independent events. If P(A) = 1/2 and P(B) = 1/2, what is P(A or B)?
- If mode = 80 and mean = 110, then median is:
- A card is drawn from a pack of 52 cards. What is the probability that it is a heart?