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Finding the Fourth Proportional to 418.88, 578.28 and 288.08

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Solution

The fourth proportional to 418.88, 578.28 and 288.08 is: 397.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.88 : 578.28 = 288.08 : x
  2. Step 2: Convert to fraction form
    418.88/578.28 = 288.08/x
  3. Step 3: Cross multiply
    418.88x = 578.28 × 288.08
  4. Step 4: Simplify right side
    418.88x = 166,590.90
  5. Step 5: Solve for x
    x = 166,590.90/418.88
  6. Step 6: Final answer
    x = 397.71

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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.