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Finding the Fourth Proportional to 508.99, 702.09 and 309.79

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Solution

The fourth proportional to 508.99, 702.09 and 309.79 is: 427.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    508.99 : 702.09 = 309.79 : x
  2. Step 2: Convert to fraction form
    508.99/702.09 = 309.79/x
  3. Step 3: Cross multiply
    508.99x = 702.09 × 309.79
  4. Step 4: Simplify right side
    508.99x = 217,500.46
  5. Step 5: Solve for x
    x = 217,500.46/508.99
  6. Step 6: Final answer
    x = 427.32

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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.