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Finding the Fourth Proportional to 645.28, 890.26 and 424.36

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Solution

The fourth proportional to 645.28, 890.26 and 424.36 is: 585.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.28 : 890.26 = 424.36 : x
  2. Step 2: Convert to fraction form
    645.28/890.26 = 424.36/x
  3. Step 3: Cross multiply
    645.28x = 890.26 × 424.36
  4. Step 4: Simplify right side
    645.28x = 377,790.73
  5. Step 5: Solve for x
    x = 377,790.73/645.28
  6. Step 6: Final answer
    x = 585.47

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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.