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Finding the Fourth Proportional to 378.15, 521.85 and 220.83

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Solution

The fourth proportional to 378.15, 521.85 and 220.83 is: 304.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.15 : 521.85 = 220.83 : x
  2. Step 2: Convert to fraction form
    378.15/521.85 = 220.83/x
  3. Step 3: Cross multiply
    378.15x = 521.85 × 220.83
  4. Step 4: Simplify right side
    378.15x = 115,240.14
  5. Step 5: Solve for x
    x = 115,240.14/378.15
  6. Step 6: Final answer
    x = 304.75

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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.