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Finding the Fourth Proportional to 210.38, 315.32 and 128.97

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Solution

The fourth proportional to 210.38, 315.32 and 128.97 is: 193.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    210.38 : 315.32 = 128.97 : x
  2. Step 2: Convert to fraction form
    210.38/315.32 = 128.97/x
  3. Step 3: Cross multiply
    210.38x = 315.32 × 128.97
  4. Step 4: Simplify right side
    210.38x = 40,666.18
  5. Step 5: Solve for x
    x = 40,666.18/210.38
  6. Step 6: Final answer
    x = 193.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.