The chart shows that output for $\square$ increased about 400% between 1921 and 1928. The chart shows that output for all three products $\square$ between 1913 and 1921.
Answer (2)
Calculate the percentage increase in output between 1921 and 1928 for each product.
Identify that Iron and steel had the highest percentage increase (approximately 2333.33%).
Determine that the output for all three products decreased between 1913 and 1921.
Conclude that the output for Iron and steel increased the most between 1921 and 1928, and the output for all three products decreased between 1913 and 1921. The chart shows that output for Iron and steel increased about 400% between 1921 and 1928. The chart shows that output for all three products decreased between 1913 and 1921.
Explanation
Understanding the Problem We are given a table showing the industrial and agricultural output (in millions of tons) for Coal, Grain, and Iron and steel in the years 1913, 1921, and 1928. Our goal is to determine which product's output increased about 400% between 1921 and 1928, and whether the output for all three products increased or decreased between 1913 and 1921.
Calculating Percentage Increase First, let's calculate the percentage increase in output between 1921 and 1928 for each product. The percentage increase is calculated as: Output in 1921 Output in 1928 − Output in 1921 × 100% For Coal: 9 35 − 9 × 100% = 9 26 × 100% ≈ 288.89% For Grain: 37.6 73.3 − 37.6 × 100% = 37.6 35.7 × 100% ≈ 94.95% For Iron and steel: 0.3 7.3 − 0.3 × 100% = 0.3 7 × 100% ≈ 2333.33%
Identifying the Closest Percentage Increase Now, we need to find which percentage increase is closest to 400%. Comparing the calculated percentage increases, we see that none of them are close to 400%. However, the question states 'about 400%', so we should consider the context. The closest value to 400% isn't immediately obvious from the calculated percentages. The problem might have an error, or it expects us to consider the closest value among the options, even if it's not very close to 400%. However, let's proceed by identifying the product with the highest percentage increase, which is Iron and steel with approximately 2333.33%. This is significantly different from 400%.
Let's re-examine the question. It asks for the output that increased about 400% . Since none of the increases are about 400%, let's look for the one that increased the most . Iron and steel increased by more than a factor of 20, while the others increased by less than a factor of 3. Therefore, Iron and steel had the largest relative increase. However, there seems to be a mistake in the problem, as none of the options increased by about 400%. We will proceed assuming the question meant 'increased the most'.
Determining Increase or Decrease Next, we need to determine whether the output for each product increased or decreased between 1913 and 1921. We compare the output values for each product in those years:
Coal: 29.0 (1913) vs 9.0 (1921) - Decreased Grain: 80.0 (1913) vs 37.6 (1921) - Decreased Iron and steel: 8.5 (1913) vs 0.3 (1921) - Decreased
So, the output for all three products decreased between 1913 and 1921.
Final Answer Based on our calculations, the output for Iron and steel increased the most between 1921 and 1928 (approximately 2333.33%), although it is not about 400%. The output for all three products decreased between 1913 and 1921.
Examples
Understanding percentage changes is crucial in finance. For example, if you invest $1,000 in a stock and it increases by 10% in the first year and then decreases by 5% in the second year, you can calculate the net gain or loss. In the first year, your investment increases by $1,000 * 0.10 = $100, so you have $1,100. In the second year, it decreases by $1,100 * 0.05 = $55, leaving you with $1,045. This shows a net gain of $45, or a 4.5% increase over the initial investment. This type of calculation is also useful in understanding economic growth, inflation rates, and business performance.
Iron and Steel showed an increase of about 2333.33% from 1921 to 1928, which is significantly higher than the 400% mentioned. All three products decreased in output between 1913 and 1921. Thus, while the Iron and Steel output surged, the overall trend was a decrease prior to that period.
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