## horsegirl27 one year ago Medal and fan, please help out! Question will be posted below vvv

1. horsegirl27

You are ordering a meal and have $15 to spend. The restaurant charges 6% sales tax. You plan to leave a 15% tip. The equation c=x+0.06x+0.15x gives the total cost c of your meal, where x is the cost before tax and tip. What is the maximum amount you can spend before tax and tip? So, I'll be able to do the math, I'm just not a 100% sure of how to start. 2. anonymous You just have to find x. 3. anonymous It says in the problem that x is the cost before tax and tip, so the set c to 15 and solve for x. 4. horsegirl27 Well I understand that, and I understand how to find it, but I'm just slightly confused by my first step. it'll be clear once I understand it. Mind explaining and getting me on the right track? 5. anonymous Oh, in the calculation? 6. horsegirl27 Yes 7. anonymous I would add up all the xs. x + 0.06x + 0.15x = 1.21x so 15 = 1.21x 8. horsegirl27 Oh ok, thank you!! I can take it from here! Hold on and I'll show you what I get. 9. horsegirl27 I got 12.4 (rounded up) 10. anonymous Actually, 12.39 because it should go to cents, and you're looking for the maximum so you shouldn't round up on the cent 11. horsegirl27 oh, ok, thank you!! Could you explain another? 12. anonymous Yeah! 13. horsegirl27 Thanks! One moment, let me type it :) 14. horsegirl27 You have$85 in your bank account. Each week you plan to deposit $8 from your allowance and$15 from your paycheck. The equation b=85+(15+8)w gives the amount b in your bank account after w weeks. How many weeks from now will you have \$175 in your bank account? Again, I can do the math, I just need help getting started.

15. anonymous

175 = 85 + (15 + 8)w If I were you, I would gather like terms. This is one way to do it: 175 - 85 = 23w 90 = 23w

16. horsegirl27

Ok, thanks! Let me finish that one, and i'll check with you.

17. horsegirl27

3.91=w, correct?

18. anonymous

yes. I got that too :) If you don't know how to start, you should add the xs together and the numbers together.

19. horsegirl27

Ok, thanks. So always combine like terms, got it.

20. horsegirl27

One more? This one is different. It's fractions, and I always get myself mixed up with those.

21. anonymous

Yeah, I used to hate fractions XD

22. horsegirl27

Haha they are quite a pain. 2/3(c-18)=7 (the 2 is over the 3, the parentheses are next to that)

23. horsegirl27

$$\Large \frac{2}{3} (c-18) =7$$ $$\Large \frac{2}{3}c - \frac{2}{3}(18) =7$$ $$\Large \frac{2}{3}c - \frac{2}{1}(6) =7$$ $$\Large \frac{2}{3}c - (12) =7$$ $$\Large \frac{2}{3}c =19$$ $$\Large c= 19* \frac{3}{2}$$