(18) A store has 4 bins of planet posters with 23 poster in each bin. It has 3 bins of planet calendars with 26 calendars in each bin. Yesterday, 72 calendars sold. How many planet posters and calendars are in all? Explain how you found your answer, and \( h \) you know if your answer is reasonable.

To solve the problem, we need to calculate the total number of planet posters and calendars in the store. Let's break it down step by step. ### Step 1: Calculate the total number of planet posters The store has 4 bins of planet posters, and each bin contains 23 posters. We can calculate the total number of posters using the formula: \[ \text{Total Posters} = \text{Number of Bins} \times \text{Posters per Bin} \] Substituting the known values: \[ \text{Total Posters} = 4 \times 23 \] ### Step 2: Calculate the total number of planet calendars The store has 3 bins of planet calendars, and each bin contains 26 calendars. We can calculate the total number of calendars using a similar formula: \[ \text{Total Calendars} = \text{Number of Bins} \times \text{Calendars per Bin} \] Substituting the known values: \[ \text{Total Calendars} = 3 \times 26 \] ### Step 3: Calculate the total number of items Now, we will add the total number of posters and calendars together to find the overall total: \[ \text{Total Items} = \text{Total Posters} + \text{Total Calendars} \] ### Step 4: Perform the calculations Let's calculate the total number of posters and calendars. 1. Calculate the total number of posters: \[ \text{Total Posters} = 4 \times 23 = 92 \] 2. Calculate the total number of calendars: \[ \text{Total Calendars} = 3 \times 26 = 78 \] 3. Calculate the total number of items: \[ \text{Total Items} = 92 + 78 = 170 \] ### Conclusion The total number of planet posters and calendars in the store is \( 170 \). ### Reasonableness Check To check if the answer is reasonable, we can consider the following: - The number of posters (92) and calendars (78) both seem reasonable given the number of bins and items per bin. - Adding these two numbers gives us a total of 170, which is a reasonable total for a store's inventory. Thus, the final answer is that there are \( 170 \) planet posters and calendars in all.