Final answer:
To find the number of people under 50 at the family reunion, set up a system of equations using x to represent the number of people 50 or older. Since there are 3 times as many people under 50, the number of people under 50 can be represented by 3x. Solve the equation to find the value of x, and then calculate the number of people under 50 by multiplying x by 3.
Step-by-step explanation:
To find the number of people under 50, we need to set up a system of equations. Let x represent the number of people 50 or older. Since there are 3 times as many people under 50, the number of people under 50 can be represented by 3x. The total number of people at the reunion is 68. So we can write an equation: x + 3x = 68. Combining like terms, we get 4x = 68. Dividing both sides by 4, we find that x = 17. Therefore, there are 3 * 17 = 51 people under 50 at the reunion.