Answer:
There was an initial balance of at least $60 on Peter's gift card.
Step-by-step explanation:
Inequalities
Is a relation that makes a non-equal comparison between two mathematical expressions. Usual comparators are >, <, ≠, ≤, and ≥.
Let's call x to the original amount Peter had on his gift card balance. We know he spent half of it on coffee. Thus the remaining balance is x/2.
He loaded $10 to his balance, so the new balance is x/2+10. Knowing he now has at least $40, we set the inequality as:
x/2+10 ≥40
Subtracting 10:
x/2 ≥40-10
Operating:
x/2 ≥30
Multiplying by 2:
x≥60
There was an initial balance of at least $60 on Peter's gift card.
