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Finding the Fourth Proportional to 645.57, 890.29 and 424.74

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Solution

The fourth proportional to 645.57, 890.29 and 424.74 is: 585.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.57 : 890.29 = 424.74 : x
  2. Step 2: Convert to fraction form
    645.57/890.29 = 424.74/x
  3. Step 3: Cross multiply
    645.57x = 890.29 × 424.74
  4. Step 4: Simplify right side
    645.57x = 378,145.64
  5. Step 5: Solve for x
    x = 378,145.64/645.57
  6. Step 6: Final answer
    x = 585.75

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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.