Industrial and Agricultural Output (In Millions of Tons)
\begin{tabular}{|c|c|c|c|}
\hline & 1913 & 1921 & 1928 \\
\hline Coal & 29.0 & 9.0 & 35.0 \\
\hline Grain & 80.0 & 37.6 & 73.3 \\
\hline \begin{tabular}{c}
Iron and \\
steel
\end{tabular} & 8.5 & 0.3 & 7.3 \\
\hline
\end{tabular}

The chart shows that coal output increased by about [tex]400\%[/tex] between 1921 and 1928. The chart shows the output for all three products between 1913 and 1928.



Answer :

Alright, let's solve the problem step-by-step. We need to find the percentage decrease in the output for each of the three products (coal, grain, and iron/steel) between 1913 and 1921. We'll follow a systematic approach to determine the percentage decrease for each product.

### Step 1: Understand the Given Data
We have the following production outputs in millions of tons:

Year 1913:
- Coal: 29.0 million tons
- Grain: 80.0 million tons
- Iron and Steel: 8.5 million tons

Year 1921:
- Coal: 9.0 million tons
- Grain: 37.6 million tons
- Iron and Steel: 0.3 million tons

### Step 2: Calculate the Decrease in Output
To find the percentage decrease, we'll use the formula:
[tex]\[ \text{Percentage Decrease} = \left( \frac{\text{Initial Value} - \text{Final Value}}{\text{Initial Value}} \right) \times 100 \][/tex]

Let's apply this formula to each product.

#### Coal:
- Initial Value (1913): 29.0 million tons
- Final Value (1921): 9.0 million tons

[tex]\[ \text{Percentage Decrease for Coal} = \left( \frac{29.0 - 9.0}{29.0} \right) \times 100 \][/tex]

#### Grain:
- Initial Value (1913): 80.0 million tons
- Final Value (1921): 37.6 million tons

[tex]\[ \text{Percentage Decrease for Grain} = \left( \frac{80.0 - 37.6}{80.0} \right) \times 100 \][/tex]

#### Iron and Steel:
- Initial Value (1913): 8.5 million tons
- Final Value (1921): 0.3 million tons

[tex]\[ \text{Percentage Decrease for Iron and Steel} = \left( \frac{8.5 - 0.3}{8.5} \right) \times 100 \][/tex]

### Step 3: List the Calculated Values
From the calculations, the percentage decreases are as follows:
- Coal: 68.97%
- Grain: 53.00%
- Iron and Steel: 96.47%

### Conclusion:
The output for coal decreased by approximately 68.97%, for grain by 53.00%, and for iron and steel by 96.47% between 1913 and 1921. These results demonstrate that there was a significant reduction in the production of these three products over the given time period.