9514 1404 393
Answer:
9. x = $7.80
10. 440 miles
Explanation:
9. The relationship is proportional. Each taco costs $2.60/2 = $1.30. The cost of 6 tacos can be found by doubling the cost of 3 tacos:
x = 6-taco cost = 2 × 3-taco cost = 2 × $3.90
x = $7.80
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10. Apparently, we're to assume that miles driven is proportional to gallons used. Then we can drive m miles on 20 gallons of gas, where ...
m/20 = 330/15
m = (20/15)(330) = (4/3)(330)
m = 440
440 miles can be driven on 20 gallons of gas.