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Finding the Fourth Proportional to 650.80, 898.12 and 388.78

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Solution

The fourth proportional to 650.80, 898.12 and 388.78 is: 536.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    650.80 : 898.12 = 388.78 : x
  2. Step 2: Convert to fraction form
    650.80/898.12 = 388.78/x
  3. Step 3: Cross multiply
    650.80x = 898.12 × 388.78
  4. Step 4: Simplify right side
    650.80x = 349,171.09
  5. Step 5: Solve for x
    x = 349,171.09/650.80
  6. Step 6: Final answer
    x = 536.53

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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.