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Finding the Fourth Proportional to 501.21, 747.47 and 428.54

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Solution

The fourth proportional to 501.21, 747.47 and 428.54 is: 639.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.21 : 747.47 = 428.54 : x
  2. Step 2: Convert to fraction form
    501.21/747.47 = 428.54/x
  3. Step 3: Cross multiply
    501.21x = 747.47 × 428.54
  4. Step 4: Simplify right side
    501.21x = 320,314.91
  5. Step 5: Solve for x
    x = 320,314.91/501.21
  6. Step 6: Final answer
    x = 639.08

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.