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Finding the Fourth Proportional to 651.20, 976.80 and 285.68

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Solution

The fourth proportional to 651.20, 976.80 and 285.68 is: 428.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    651.20 : 976.80 = 285.68 : x
  2. Step 2: Convert to fraction form
    651.20/976.80 = 285.68/x
  3. Step 3: Cross multiply
    651.20x = 976.80 × 285.68
  4. Step 4: Simplify right side
    651.20x = 279,052.22
  5. Step 5: Solve for x
    x = 279,052.22/651.20
  6. Step 6: Final answer
    x = 428.52

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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.