Find the Probability of One Event or a Second Event Occurring
-Given the sequence 3, 4, 5, 6 ... 42, what is the probability that a number in the sequence is even or that it is greater than 12 and less then 27?
A) $\frac { 27 } { 40 }$
B) $\frac { 17 } { 20 }$
C) $\frac { 53 } { 80 }$
D) $\frac { 53 } { 78 }$

Question

Find the Probability of One Event or a Second Event Occurring
-Given the sequence 3, 4, 5, 6 ... 42, what is the probability that a number in the sequence is even or that it is greater than 12 and less then 27? 
A) $\frac { 27 } { 40 }$
B) $\frac { 17 } { 20 }$
C) $\frac { 53 } { 80 }$
D) $\frac { 53 } { 78 }$

Quizplus · Accepted Answer

The sequence from 3 to 42 has 40 numbers. The even numbers in this sequence are every other number, so there are 20 even numbers. The numbers greater than 12 and less than 27 are 13 through 26, which are 14 numbers. However, 7 of these are even (14, 16, 18, 20, 22, 24, 26), which we've already counted. So, we add the unique odd numbers in this range (7) to the total even numbers (20) to avoid double-counting, giving us 27 unique numbers that meet either condition. Thus, the probability is $\frac{27}{40}$.

Find the Probability of One Event or a Second Event 2740\frac { 27 } { 40 }4027​

Find the Probability of One Event or a Second Event $\frac { 27 } { 40 }$