Let's represent the amount of additional money Ronald needs as "x". The inequality that represents the situation is:
21 + x ≥ 48
To solve the inequality, we can subtract 21 from both sides of the equation:
x ≥ 48 - 21
Simplifying:
x ≥ 27
So Ronald needs at least $27 more to have a total of $48.
To graph the solution, we can represent the value of "x" on the horizontal axis and draw a solid line at x = 27 to indicate that it includes the value of 27. Then, shade the region to the right of the line to represent all the values of "x" that are greater than or equal to 27.