Price Relative Calculation:
To calculate the price relative, we need to compare the prices of a commodity in different years. In this case, we are comparing the prices in the years 1975 and 1980.

The price relative is calculated using the formula:

Price Relative = (Price in the selected year / Price in the base year) * 100

Calculation:
Using the given data, we can calculate the price relative for the year 1975 and 1980.

For the year 1975:
Price Relative = (Price in 1975 / Price in 1980) * 100
= (25 / 30) * 100
= 83.33

For the year 1980:
Price Relative = (Price in 1980 / Price in 1980) * 100
= (30 / 30) * 100
= 100

Interpretation:
The price relative is a measure that compares the price of a commodity in a selected year with the price of the same commodity in a base year.

In this context, the base year is 1980. Therefore, the price relative for the year 1980 is always 100, as it is the reference point for comparison.

The price relative for the year 1975 is 83.33. This means that the price of the commodity in 1975 was 83.33% of the price in the base year 1980.

Significance:
Price relative is a useful tool in analyzing and comparing the changes in prices over time. It allows us to understand the relative change in prices and their impact on the economy.

By using a base year, we can track the changes in prices relative to a fixed point. This helps in measuring inflation or deflation, analyzing purchasing power, and making economic forecasts.

Price relatives are often used to construct various economic indicators such as price indices, which further help in understanding the overall price level and its impact on the economy.

Conclusion:
In this case, the price relative for the year 1975 is 83.33, indicating that the price of the commodity in 1975 was 83.33% of the price in the base year 1980. The price relative for the year 1980 is always 100, as it is the reference point for comparison. Price relatives are important tools in analyzing and understanding changes in prices over time, and they play a crucial role in various economic indicators and analyses.

120 is the right answer
30/25×100 = 120