An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (1)
Calculate the percentage increase for each product between 1921 and 1928.
Determine which percentage increase is closest to 400%.
Compare the output of each product between 1913 and 1921 to see if it increased or decreased.
State that the output for Coal increased closest to 400% (approximately 288.89%) and the output for all three products decreased between 1913 and 1921. The final answer is: Coal, decreased.
Explanation
Understanding the Problem The problem provides 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. We need to determine which product's output increased approximately 400% between 1921 and 1928, and whether the output of 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.
For Coal: Percentage increase = 9.0 35.0 − 9.0 × 100% For Grain: Percentage increase = 37.6 73.3 − 37.6 × 100% For Iron and steel: Percentage increase = 0.3 7.3 − 0.3 × 100%
Computing the Increases Now, let's compute these percentage increases:
Coal increase: 9.0 35.0 − 9.0 × 100% = 9 26 × 100% ≈ 288.89% Grain increase: 37.6 73.3 − 37.6 × 100% = 37.6 35.7 × 100% ≈ 94.95% Iron and steel increase: 0.3 7.3 − 0.3 × 100% = 0.3 7 × 100% ≈ 2333.33%
Comparing 1913 and 1921 Outputs Comparing these percentage increases to 400%, we see that none of them are approximately 400%. However, the question states that the output increased about 400% between 1921 and 1928. Among the three, Coal's increase of approximately 288.89% is the closest to 400% if we consider a very loose interpretation of 'about'. However, it's important to note that none of the increases are actually close to 400%.
Now, let's compare the output of each product in 1913 and 1921 to determine if it increased or decreased:
For Coal: 1913 output = 29.0, 1921 output = 9.0. The output decreased. For Grain: 1913 output = 80.0, 1921 output = 37.6. The output decreased. For Iron and steel: 1913 output = 8.5, 1921 output = 0.3. The output decreased.
Determining the Trend Since the output of Coal decreased from 29.0 to 9.0, Grain decreased from 80.0 to 37.6, and Iron and steel decreased from 8.5 to 0.3 between 1913 and 1921, the output for all three products decreased between 1913 and 1921.
Final Answer Based on our calculations, the output for Coal increased about 288.89% between 1921 and 1928, which is the closest to the stated 400% (although not very close). The output for all three products decreased between 1913 and 1921.
Examples
Understanding percentage changes in production is crucial in economics and business. For example, if a company's revenue increases by 50% over a year, it indicates strong growth. Similarly, tracking agricultural output helps governments ensure food security and plan resource allocation. These calculations are essential for making informed decisions about investments, production, and policy-making.
