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Finding the Fourth Proportional to 530.30, 731.90 and 309.31

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Solution

The fourth proportional to 530.30, 731.90 and 309.31 is: 426.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    530.30 : 731.90 = 309.31 : x
  2. Step 2: Convert to fraction form
    530.30/731.90 = 309.31/x
  3. Step 3: Cross multiply
    530.30x = 731.90 × 309.31
  4. Step 4: Simplify right side
    530.30x = 226,382.93
  5. Step 5: Solve for x
    x = 226,382.93/530.30
  6. Step 6: Final answer
    x = 426.89

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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.