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Finding the Fourth Proportional to 615.15, 847.87 and 393.75

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Solution

The fourth proportional to 615.15, 847.87 and 393.75 is: 542.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.15 : 847.87 = 393.75 : x
  2. Step 2: Convert to fraction form
    615.15/847.87 = 393.75/x
  3. Step 3: Cross multiply
    615.15x = 847.87 × 393.75
  4. Step 4: Simplify right side
    615.15x = 333,847.83
  5. Step 5: Solve for x
    x = 333,847.83/615.15
  6. Step 6: Final answer
    x = 542.71

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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.