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Finding the Fourth Proportional to 509.05, 702.43 and 287.98

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Solution

The fourth proportional to 509.05, 702.43 and 287.98 is: 397.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    509.05 : 702.43 = 287.98 : x
  2. Step 2: Convert to fraction form
    509.05/702.43 = 287.98/x
  3. Step 3: Cross multiply
    509.05x = 702.43 × 287.98
  4. Step 4: Simplify right side
    509.05x = 202,288.63
  5. Step 5: Solve for x
    x = 202,288.63/509.05
  6. Step 6: Final answer
    x = 397.39

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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.