Grace has $6 to buy a gallon of milk and some apples.
The gallon of milk costs $3.59.
Each apple costs 50 cents, that is, $0.50.
In order to determine how many apples Graca can buy. You consider that the cost of milk and apples must be lower or equal that $6 (because is the money that Grace has). If x is the variable for the number of apples. You can write the previous situation in an algebraic way as follow:
3.59 + 0.50x ≤ 6
milk price plus cost of x apples must be lower or equal than 6
To solve the previous inequality you proceed as follow:
3.59 + 0.50x ≤ 6 subtracut 3.59 both sides
0.50x ≤ 6 - 3.59
0.50x ≤ 2.41 divide by 0.50 both sides
x ≤ 2.41/0.50
x ≤ 4.82
Of course, there are no 4.82 apples, so, you approximate to the lower integer:
x ≤ 4.82
Hence, Grace can buy 4 applesc