Using inequalities to solve problems | Solving equations & inequalities | Algebra I | Khan Academy

TL;DR

Kayla wants to visit a friend and wants to know the maximum number of subway stops she can afford.

Transcript

• [Instructor] We're told that Kayla wants to visit a friend who lives eight kilometers away. She'll ride the subway as far as she can before walking the rest of the way. First, she needs to buy an access pass that costs $5.50. There's also a fee of $1.25 per stop. This is an expensive subway. Kayla doesn't want to spend more than $15 on the trip. ... Read More

Key Insights

• 😒 Kayla wants to visit a friend who lives 8 kilometers away and will use the subway for part of the journey.
• ✋ She needs to purchase an access pass for $5.50 and there is an additional fee of $1.25 per stop.
• 😫 Kayla sets a budget of $15 and wants to determine the maximum number of stops she can take without exceeding it.
• ✋ The inequality equation 5.50 + 1.25S <= 15 is used to calculate the maximum number of stops.
• ✋ Solving the equation reveals that Kayla can afford a maximum of seven stops.
• ✋ Taking fractional stops is not allowed, so the largest whole number of stops is chosen.

Questions & Answers

Q: How much does Kayla need to spend upfront for the trip?

Kayla needs to spend $5.50 upfront for the access pass.

Q: What is the cost per stop on the subway?

The cost per stop on the subway is $1.25.

Q: What is the inequality equation to determine the number of stops Kayla can afford?

The inequality equation is 5.50 + 1.25S <= 15, where S represents the number of stops.

Q: What is the largest number of stops Kayla can afford?

Kayla can afford a maximum of seven stops on her trip.

Summary & Key Takeaways

• Kayla wants to visit a friend who lives 8 kilometers away and will be using the subway.

• She needs to buy an access pass for $5.50 and there's a fee of $1.25 per stop.

• Kayla wants to spend less than $15 and wants to know the largest number of stops she can afford.