Answer:
The inequality is : "x < 23" which agrees with answer "D" in your list
Step-by-step explanation:
Notice that the number of cookies that Susan bakes is the unknown "x".
Since her sister bakes 24 more cookies than what susan does, then the sister makes:
Sister = x + 24
Let's now write the number of cookies that both bake which should be the addition of both quantities: x (what Susan bakes) plus "x+24" (what her sister makes): x + x + 24 = 2 x + 24
Now we write in math terms that this expression should be less (<) than 70 - Notice that the problem says "less than 7", and not "less than or equal 7", so the strictly less than symbol applies:
2 x + 24 < 70
and work to isolate "x" on one side of the inequality, by first subtracting 24 from both sides:
2 x < 70 - 24
2 x < 46
and then dividing both sides by "2" to leave just "x" on the left:
2 x / 2 < 46 / 2
x < 23
