Can somehow help justify if my solutions to the problem below is correct and guide me on (b)?

Question

Can somehow help justify if my solutions to the problem below is correct and guide me on (b)?

2 Answers

Impact of this question

2024 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2016-10-19T11:40:50

The customer must travel $6 2/3$ Km to reduce average cost at $80$ cents/kilometer.

Explanation:

b) let x be the asked kilometer for average cost at 80 cents per kilometer. Then $x*0.80 = 2+(0.50*x) or 0.80x-0.50x=2 or0.30x=2 or x=2/3*10 =20/3=6 2/3 km$ [Ans]

Answer 2 · 2016-10-19T13:29:40

For a distance of $6 2/3$ km the average cost will be $80c$

Explanation:

$x$ is the number of Km travelled.

The total cost of travelling $x$ km is calculated as:

$50c" per km" + $2" "larr 50c = $0.50$

$darr" "darr " "darr$

$0.5xx ""x" "+2 = 0.5x+2$

To find the average cost per Km:
divide the total cost by the number of Km travelled.

Ave cost = $f(x) = (0.5x+2)/x$

The average cost for $x$ km should be $80c rarr $0.8$

$(0.5x+2)/x = 0.8" "larr xx x$

$0.5x +2 = 0.8x" "larr$ move x-terms to the right

$2 = 0.8x-0.5x$

$2 = 0.3x" "larr$ divide by 0.3

$2/0.3 = x$

$20/3 = x$

$x = 6 2/3$

For a distance of $6 2/3$ km the average cost will be $80c$

Science

Math

Humanities

... and beyond

Can somehow help justify if my solutions to the problem below is correct and guide me on (b)?

2 Answers

Explanation:

Explanation:

Related questions

Impact of this question