Answered

Discover the best answers at Westonci.ca, where experts share their insights and knowledge with you. Join our platform to get reliable answers to your questions from a knowledgeable community of experts. Discover in-depth answers to your questions from a wide network of professionals on our user-friendly Q&A platform.

A mobile phone company offers two monthly calling plans, A and B. Under A, every minute costs $ 0.10. Under B, the first 100 minutes costs $ 12 and every extra minute costs $ 0.08. What monthly talking time would make B the better choice?

Sagot :

A 1min = $0.10
A 100min = $0.10 x 100 = $10
B 100min = $12
B-A = $2
101th min onwards:
A 1 min = $0.10
B 1 min = $0.08
A-B = $0.02

$2 / $0.02 = 100 min
A 200 min = $0.10 x 200 = $20
B 200 min = $12 + ($0.08 x 100) = $20

A 201 min = $20.10
B 201 min = $20.08

Monthly talking time should be 201 minutes and above for B to be the better choice

naǫ
x - talking time in minutes
y - price

A:
[tex]y=0.1x[/tex]

B:
[tex]y=12+(x-100)\cdot0.08 \\ y=12+0.08x-8 \\ y=0.08x+4[/tex]

B price must be less than A so:
[tex]0.08x+4 < 0.1x \\ 4 < 0.1x-0.08x \\ 4 < 0.02x \\ 200 < x \\ x>200[/tex]

More than 200 minutes of talking would make B the better choice.
We appreciate your visit. Hopefully, the answers you found were beneficial. Don't hesitate to come back for more information. Your visit means a lot to us. Don't hesitate to return for more reliable answers to any questions you may have. Thank you for visiting Westonci.ca. Stay informed by coming back for more detailed answers.