Answer:
When any value will make the expression equivalent when evaluated.
Step-by-step explanation:
Answer:
Cory bought 6.47 gallons
rate of change is $2.78 per gallon
Step-by-step explanation:
cost of gas per gallon = $2.78
it means that if one buy 1 gallon he will have to pay $2.78 and similary for each increase in 1 gallon of gallon gas he will have to pay $2.78.
Thus, rate of change is cost of gas per gallon as cost to buy gas changes with the change in quantity of gallon.
Let the quantity of gas bought be x gallon.
Total cost for x gallons = cost of gas per gallon*x = 2.78x
Given that total money paid by him is $18
2.78x = 18
x = 18/2.78 = 6.47
Thus, Cory bought 6.47 gallons
rate of change is $2.78 per gallon
Plan A costs a total of $95 since it says $95 for unlimited talk and text.
Plan B:
(.10 x 800) + (.05 x 1000)
The (.10 x 800) represents 10 cents per talk minute for 800 minutes.
The (.05 x 1000) represents 5 cents per text message for 1000 text messages.
Solve:
.10 x 800 = 80
.05 x 1000 = 50
80 + 50 = 130
This means Plan B will cost him $130 under these conditions.
Plan C:
20 + ((.05 x 800)+(.05 x 1000))
The 20 + represents a flat rate of $20 per month.
The (.05 x 800) represents 5 cents per call minute.
The (.05 x 1000) represents 5 cents per text.
Solve:
.05 x 800 = 40
.05 x 1000 = 50
20 + 40 + 50 = 110
This means Plan C will cost him $110 under these conditions.
Plan D:
45 + (.10(800 - 500))
The 45 + represents a flat monthly rate of $45.
The (800 - 500) represents how many minutes he has to pay for with the 500 free.
The .10 is the cost per extra minute.
Solve:
800 - 500 = 300
.10 x 300 = 30
45 + 30 = 75
This means Plan D will cost him $75 under these conditions.
In short:
Plan A- $95
Plan B- $130
Plan C- $110
Plan D- $75
The least expensive among these is Plan D, which only costs $75 per month.
Answer: sin(34) = 0.52908268612
The percent decrease is 80% or 80 percent
