Question

each spinner is spun once to make a 2 - digit number. the result of the first spinner will be the digit in the tens place. the result of the second spinner will be the digit in the ones place. a spin of 3 and 2 would be 32 the tree diagram shows the possible outcomes. what is the probability that the 2 - digit number will be less than 20? probability

Explanation:

Step1: Find total number of outcomes

Each spinner has 3 options. By the fundamental counting principle, the total number of 2 - digit numbers formed is $3\times3=9$.

Step2: Find favorable outcomes

For a 2 - digit number to be less than 20, the tens - digit must be 1. When the tens - digit is 1 (from the first spinner), the second spinner has 3 possible outcomes (1, 2, 3). So there are 3 favorable outcomes.

Step3: Calculate probability

The probability $P$ of an event is given by the formula $P=\frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}}$. So $P = \frac{3}{9}=\frac{1}{3}$.

Answer:

$\frac{1}{3}$