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Finding the Fourth Proportional to 657.87, 907.85 and 378.09

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Solution

The fourth proportional to 657.87, 907.85 and 378.09 is: 521.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.87 : 907.85 = 378.09 : x
  2. Step 2: Convert to fraction form
    657.87/907.85 = 378.09/x
  3. Step 3: Cross multiply
    657.87x = 907.85 × 378.09
  4. Step 4: Simplify right side
    657.87x = 343,247.12
  5. Step 5: Solve for x
    x = 343,247.12/657.87
  6. Step 6: Final answer
    x = 521.76

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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.