Add or subtract. i. 16 + 0 = 16
ii. 0 - 7 = 0 + (-7) = -7
iii. -4 + 0 = -4
iv. 0 + d = d
v. What pattern do you notice in parts (i) through (iv)?

Mrs. gehrke said cheddar weighs 16.8 pounds. he actually weighs 15.2 pounds. what is the percent error?

Andy has $310 in his account. each week, w, he withdraws $30 for his expenses. which expression could be used if he wanted to find out how much money he had left after 8 weeks?

Ashley spent half of her lunch money on a turkey sandwich. then she spent two-thirds of the money she had left on a bottle of juice and the rest of the money on a cookie. if the cookie cost $.75, how much lunch money did ashley have to start with?