Question

What equation can you write to see if Krystal and Desmond will ever have the same amount of money in their accounts?
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1 point
Choose
When will Krystal and Desmond have the same amount of money in their accounts?
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1 point
Never - their linear graphs would be parallel
After 3.5 hours, they will have the same amount
They will always have the same amount as their graphs are the same
After 5 hours, they will have the same amount
A teacher is choosing between two options for a class field trip to an orchard.
• At Orchard A, admission costs $9 per person, and 3 chaperones are required.
• At Orchard B, the cost is $10 per person, but only 1 chaperone is required.
• At each orchard, the same price applies to both chaperones and students.
What does the solution to the inequality 9(n + 3) < 10(n + 1) tell us?
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Answer 1

1) Equation to see if Krystal and Desmond will ever have the same amount:
Let K0 and D0 be their starting amounts and rK and rD their rates (per hour). Write
K0 + rK·t = D0 + rD·t.
If rK ≠ rD, solve t = (D0 − K0) / (rK − rD). If rK = rD and K0 ≠ D0, they never match; if rK = rD and K0 = D0, they always have the same amount.

2) About the multiple-choice question: you need the specific starting amounts and rates for Krystal and Desmond to pick one of those answers. With those numbers you can plug them into the equation above and solve for t.

3) Interpretation of 9(n + 3) < 10(n + 1):
Compute: 9n + 27 < 10n + 10 → 27 − 10 < 10n − 9n → 17 < n, so n > 17.
This means Orchard A is cheaper than Orchard B when there are more than 17 students (i.e., at least 18 students, since n must be an integer).