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Finding the Fourth Proportional to 280.72, 418.60 and 278.28

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Solution

The fourth proportional to 280.72, 418.60 and 278.28 is: 414.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.72 : 418.60 = 278.28 : x
  2. Step 2: Convert to fraction form
    280.72/418.60 = 278.28/x
  3. Step 3: Cross multiply
    280.72x = 418.60 × 278.28
  4. Step 4: Simplify right side
    280.72x = 116,488.01
  5. Step 5: Solve for x
    x = 116,488.01/280.72
  6. Step 6: Final answer
    x = 414.96

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.