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Finding the Fourth Proportional to 630.91, 870.65 and 354.91

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Solution

The fourth proportional to 630.91, 870.65 and 354.91 is: 489.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.91 : 870.65 = 354.91 : x
  2. Step 2: Convert to fraction form
    630.91/870.65 = 354.91/x
  3. Step 3: Cross multiply
    630.91x = 870.65 × 354.91
  4. Step 4: Simplify right side
    630.91x = 309,001.10
  5. Step 5: Solve for x
    x = 309,001.10/630.91
  6. Step 6: Final answer
    x = 489.77

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.