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Finding the Fourth Proportional to 509.21, 702.71 and 285.15

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Solution

The fourth proportional to 509.21, 702.71 and 285.15 is: 393.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.21 : 702.71 = 285.15 : x
  2. Step 2: Convert to fraction form
    509.21/702.71 = 285.15/x
  3. Step 3: Cross multiply
    509.21x = 702.71 × 285.15
  4. Step 4: Simplify right side
    509.21x = 200,377.76
  5. Step 5: Solve for x
    x = 200,377.76/509.21
  6. Step 6: Final answer
    x = 393.51

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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.