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Finding the Fourth Proportional to 421.13, 630.75 and 339.10

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Solution

The fourth proportional to 421.13, 630.75 and 339.10 is: 507.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.13 : 630.75 = 339.10 : x
  2. Step 2: Convert to fraction form
    421.13/630.75 = 339.10/x
  3. Step 3: Cross multiply
    421.13x = 630.75 × 339.10
  4. Step 4: Simplify right side
    421.13x = 213,887.33
  5. Step 5: Solve for x
    x = 213,887.33/421.13
  6. Step 6: Final answer
    x = 507.89

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.