Question

45 children attend preschool. The number of two-year-olds is one half the number of three-year-olds. The number of four-year-olds is the same number of three-year-olds. How many two-year-olds attend the preschool? How many three-year-olds attend the preschool? How many four-year-olds attend the preschool?

Answer 1

Answer: 9 - 2 yr olds, 18 - 3 yr olds, and 18 - 4 yr olds

Step-by-step explanation:

2 yr olds: $\dfrac{1}{2}x$

3 yr olds:  x

4 yr olds:  x

2 yr olds + 3 yr olds + 4 yr olds = Total students

  $\dfrac{1}{2}x$    +       x        +       x       =        45

$2\dfrac{1}{2}x = 45\\\\\dfrac{5}{2}x = 45\\\\5x = 90\\\\x = 18$