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Finding the Fourth Proportional to 652.40, 978.92 and 287.15

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Solution

The fourth proportional to 652.40, 978.92 and 287.15 is: 430.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    652.40 : 978.92 = 287.15 : x
  2. Step 2: Convert to fraction form
    652.40/978.92 = 287.15/x
  3. Step 3: Cross multiply
    652.40x = 978.92 × 287.15
  4. Step 4: Simplify right side
    652.40x = 281,092.70
  5. Step 5: Solve for x
    x = 281,092.70/652.40
  6. Step 6: Final answer
    x = 430.86

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.