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Finding the Fourth Proportional to 649.90, 896.56 and 387.87

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Solution

The fourth proportional to 649.90, 896.56 and 387.87 is: 535.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.90 : 896.56 = 387.87 : x
  2. Step 2: Convert to fraction form
    649.90/896.56 = 387.87/x
  3. Step 3: Cross multiply
    649.90x = 896.56 × 387.87
  4. Step 4: Simplify right side
    649.90x = 347,748.73
  5. Step 5: Solve for x
    x = 347,748.73/649.90
  6. Step 6: Final answer
    x = 535.08

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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.