Purvi and her friends tipped their waiter a total of ten dollars for dinners that cost nine dollars, eight dollars, eleven dollars and twelve dollars each. Use a percent proportion to solve for the percent tip they left the waiter. Show your work.

Question

anonymous · Answer

x/100 = $12/($9+$8+$11+$12)
 1200=40*x
 x=30%
 
olive oil=75% or 0.75
 3 = 0.75*x
 x=4 (total solution volume is 4 cups)
 
$80,000*0.15=$12,000
 $12,000+$40,000=$52,000
 
$58,000 is more than $52,000 so Isabelle made more money than Randall.
 
143-130=13
 13 = 0.01*x*130
 13 = 1.3*x
 10 = x (10% increase)

anonymous · Answer

1. The total cost all dinners was $9 + $8 + $11 + $12 = $40. The amount of the tip is $12. Thus, they tipped a total of $12/$40 = 30%. That's a big tip!
 
2. 25% is 1/4, and 75% is 3/4. Therefore, to make 4 cups of furniture polish, you'd mix 1 cup of vinegar with 3 cups of olive oil.
 
3. Randall's income was $40,000 + 0.15 × $80,000 = $40,000 + $12,000 = $52,000. Isabelle's income of $58,000 was more.
 
4. The percent increase is the difference divided by the original price. Thus, the percent increase is ($143 - $130)/$130 = $13/$130 = 0.10 = 10%

anonymous · Answer

x/100 = $12/($9+$8+$11+$12)
 1200=40*x
 x=30%