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Finding the Fourth Proportional to 418.87, 577.76 and 287.65

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Solution

The fourth proportional to 418.87, 577.76 and 287.65 is: 396.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.87 : 577.76 = 287.65 : x
  2. Step 2: Convert to fraction form
    418.87/577.76 = 287.65/x
  3. Step 3: Cross multiply
    418.87x = 577.76 × 287.65
  4. Step 4: Simplify right side
    418.87x = 166,191.23
  5. Step 5: Solve for x
    x = 166,191.23/418.87
  6. Step 6: Final answer
    x = 396.76

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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.