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Finding the Fourth Proportional to 403.91, 557.20 and 279.64

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Solution

The fourth proportional to 403.91, 557.20 and 279.64 is: 385.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.91 : 557.20 = 279.64 : x
  2. Step 2: Convert to fraction form
    403.91/557.20 = 279.64/x
  3. Step 3: Cross multiply
    403.91x = 557.20 × 279.64
  4. Step 4: Simplify right side
    403.91x = 155,815.41
  5. Step 5: Solve for x
    x = 155,815.41/403.91
  6. Step 6: Final answer
    x = 385.77

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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.