Answer:
[tex]\boxed{320}[/tex]
Step-by-step explanation:
Let x = calories in chocolate bar
¼x = ¼ of the calories
¼x – 10 = 10 calories less than half the calories
¼x – 10 = 70
¼x = 80
x = 320
There are [tex]\boxed{320}[/tex] calories in the chocolate bar.