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Finding the Fourth Proportional to 649.85, 896.81 and 387.95

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Solution

The fourth proportional to 649.85, 896.81 and 387.95 is: 535.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.85 : 896.81 = 387.95 : x
  2. Step 2: Convert to fraction form
    649.85/896.81 = 387.95/x
  3. Step 3: Cross multiply
    649.85x = 896.81 × 387.95
  4. Step 4: Simplify right side
    649.85x = 347,911.02
  5. Step 5: Solve for x
    x = 347,911.02/649.85
  6. Step 6: Final answer
    x = 535.38

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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.