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Finding the Fourth Proportional to 421.35, 628.91 and 372.75

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Solution

The fourth proportional to 421.35, 628.91 and 372.75 is: 556.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.35 : 628.91 = 372.75 : x
  2. Step 2: Convert to fraction form
    421.35/628.91 = 372.75/x
  3. Step 3: Cross multiply
    421.35x = 628.91 × 372.75
  4. Step 4: Simplify right side
    421.35x = 234,424.34
  5. Step 5: Solve for x
    x = 234,424.34/421.35
  6. Step 6: Final answer
    x = 556.36

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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.