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Finding the Fourth Proportional to 689.92, 951.78 and 427.78

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Solution

The fourth proportional to 689.92, 951.78 and 427.78 is: 590.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.92 : 951.78 = 427.78 : x
  2. Step 2: Convert to fraction form
    689.92/951.78 = 427.78/x
  3. Step 3: Cross multiply
    689.92x = 951.78 × 427.78
  4. Step 4: Simplify right side
    689.92x = 407,155.24
  5. Step 5: Solve for x
    x = 407,155.24/689.92
  6. Step 6: Final answer
    x = 590.15

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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.