For example: Joey is planning a party and wants to invite at least 20 guests. He already has 12 guests confirmed. How many more guests does he need to invite to meet his goal of at least 20 guests?
Solution:
Let's the number of additional guests Joey needs to invite be x.
Total number of guests is 12+x, and she wants to have at least 20 guests in total. So the inequality 12 + x ≥ 20 represents the situation.
12 + x ≥ 20
x ≥ 20 - 12
x ≥ 8
Therefore, Joey need to invite alteast 8 more guests to meet his goal.