1. **State the problem:** We are given membership numbers of the Church of Jesus Christ of Latter-day Saints at five-year intervals from 2000 to 2015. We want to find the average number of additional members expected each year, assuming the membership increases by the same amount every year. 2. **Identify the data points:** - Year 2000: 11,100,000 members - Year 2005: 12,600,000 members - Year 2010: 14,100,000 members - Year 2015: 15,600,000 members 3. **Formula used:** To find the average increase per year, use the formula for slope (rate of change): $$\text{Rate of change} = \frac{\text{Change in membership}}{\text{Change in years}}$$ 4. **Calculate the total change in membership and years:** - From 2000 to 2015, the membership increased from 11,100,000 to 15,600,000. - Change in membership = $15,600,000 - 11,100,000 = 4,500,000$ - Change in years = $2015 - 2000 = 15$ 5. **Calculate the average increase per year:** $$\text{Average increase per year} = \frac{4,500,000}{15} = 300,000$$ 6. **Interpretation:** On average, the church membership increases by about 300,000 members each year. **Final answer:** About 300,000 additional members are expected each year.