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Finding the Fourth Proportional to 615.50, 849.16 and 405.78

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Solution

The fourth proportional to 615.50, 849.16 and 405.78 is: 559.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.50 : 849.16 = 405.78 : x
  2. Step 2: Convert to fraction form
    615.50/849.16 = 405.78/x
  3. Step 3: Cross multiply
    615.50x = 849.16 × 405.78
  4. Step 4: Simplify right side
    615.50x = 344,572.14
  5. Step 5: Solve for x
    x = 344,572.14/615.50
  6. Step 6: Final answer
    x = 559.82

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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.