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Finding the Fourth Proportional to 509, 702.32 and 287.90

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Solution

The fourth proportional to 509, 702.32 and 287.90 is: 397.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    509 : 702.32 = 287.90 : x
  2. Step 2: Convert to fraction form
    509/702.32 = 287.90/x
  3. Step 3: Cross multiply
    509x = 702.32 × 287.90
  4. Step 4: Simplify right side
    509x = 202,197.93
  5. Step 5: Solve for x
    x = 202,197.93/509
  6. Step 6: Final answer
    x = 397.25

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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.