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Finding the Fourth Proportional to 645.28, 889.97 and 424.45

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Solution

The fourth proportional to 645.28, 889.97 and 424.45 is: 585.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.28 : 889.97 = 424.45 : x
  2. Step 2: Convert to fraction form
    645.28/889.97 = 424.45/x
  3. Step 3: Cross multiply
    645.28x = 889.97 × 424.45
  4. Step 4: Simplify right side
    645.28x = 377,747.87
  5. Step 5: Solve for x
    x = 377,747.87/645.28
  6. Step 6: Final answer
    x = 585.41

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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.