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Finding the Fourth Proportional to 403.79, 557.10 and 279.47

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Solution

The fourth proportional to 403.79, 557.10 and 279.47 is: 385.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    403.79 : 557.10 = 279.47 : x
  2. Step 2: Convert to fraction form
    403.79/557.10 = 279.47/x
  3. Step 3: Cross multiply
    403.79x = 557.10 × 279.47
  4. Step 4: Simplify right side
    403.79x = 155,692.74
  5. Step 5: Solve for x
    x = 155,692.74/403.79
  6. Step 6: Final answer
    x = 385.58

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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.