Final answer:
The price index in 2016, with 2015 as the base year and an inflation rate of -4.5%, is 95.5. The base year is known and the negative inflation rate indicates decreased prices from 2015 to 2016.
Step-by-step explanation:
If 2015 is the base year and the inflation rate between 2015 and 2016 is -4.5%, the price index in 2016 would be calculated by reducing the base index of 100 by 4.5%, which equals 95.5. Therefore, option b) 95.5 is the correct answer. The base year is known, and it is given as 2015 with an index of 100. The negative inflation rate indicates that there was a decrease in the price level from 2015 to 2016.
To clarify with an example, a price index of 100 in the base year does not change even if the base year is arbitrary. If we have an inflation rate of -4.5%, it means prices have fallen by 4.5% from the base year. Therefore, to find the new price index, we subtract 4.5 from 100 (% difference calculation), which results in 95.5 as the new price index.