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Finding the Fourth Proportional to 285.44, 391.68 and 280.32

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Solution

The fourth proportional to 285.44, 391.68 and 280.32 is: 384.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.44 : 391.68 = 280.32 : x
  2. Step 2: Convert to fraction form
    285.44/391.68 = 280.32/x
  3. Step 3: Cross multiply
    285.44x = 391.68 × 280.32
  4. Step 4: Simplify right side
    285.44x = 109,795.74
  5. Step 5: Solve for x
    x = 109,795.74/285.44
  6. Step 6: Final answer
    x = 384.65

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.