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Finding the Fourth Proportional to 305.86, 421.89 and 207.58

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Solution

The fourth proportional to 305.86, 421.89 and 207.58 is: 286.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.86 : 421.89 = 207.58 : x
  2. Step 2: Convert to fraction form
    305.86/421.89 = 207.58/x
  3. Step 3: Cross multiply
    305.86x = 421.89 × 207.58
  4. Step 4: Simplify right side
    305.86x = 87,575.93
  5. Step 5: Solve for x
    x = 87,575.93/305.86
  6. Step 6: Final answer
    x = 286.33

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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.