First, you subtract 16r by 9r, which gives you 7r, so that leaves you with 8 + 7r. You cannot add a normal number and a number with a variable, so that's all you can do, so your answer is A.
Your friend uses c=50p to find the total cost, c, for the people, p, entering a local amusement park what is the unit rate and what does it represent in the context of the situation?
Money off coupons have been circulated to 300 households. only 2/5 of these were redeemed (used) in the local supermarket to get a free shampoo. what fraction of coupons were unused? (ps: write how you got the answer)