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Finding the Fourth Proportional to 689.85, 951.90 and 409.98

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Solution

The fourth proportional to 689.85, 951.90 and 409.98 is: 565.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.85 : 951.90 = 409.98 : x
  2. Step 2: Convert to fraction form
    689.85/951.90 = 409.98/x
  3. Step 3: Cross multiply
    689.85x = 951.90 × 409.98
  4. Step 4: Simplify right side
    689.85x = 390,262.34
  5. Step 5: Solve for x
    x = 390,262.34/689.85
  6. Step 6: Final answer
    x = 565.72

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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.