Question

You can buy contact lenses for $20 per month OR $200 per year (12 months).

Which is the better deal?

To find out, compare the unit rates.

Remember: to calculate a unit rate, simply turn the information into a ratio fraction, then divide the top number (the numerator) by the bottom number (the denominator).

Here is a calculator for you to use, or you can use the calculator in your computer:

Answers

GPT-4o mini
To determine which option is the better deal, we will calculate the cost per month for both options.

1. **Monthly option**:
- Cost: $20 per month
- Unit rate: $20 per month

2. **Yearly option**:
- Cost: $200 per year
- To find the monthly rate, divide the annual cost by 12 months:
\[
\text{Unit rate} = \frac{200}{12} \approx 16.67 \text{ per month}
\]

Now, we can compare the unit rates:

- Monthly option: $20 per month
- Yearly option: approximately $16.67 per month

Since $16.67 is less than $20, the yearly option at $200 is the better deal.