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Finding the Fourth Proportional to 305.59, 421.50 and 207.19

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Solution

The fourth proportional to 305.59, 421.50 and 207.19 is: 285.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.59 : 421.50 = 207.19 : x
  2. Step 2: Convert to fraction form
    305.59/421.50 = 207.19/x
  3. Step 3: Cross multiply
    305.59x = 421.50 × 207.19
  4. Step 4: Simplify right side
    305.59x = 87,330.59
  5. Step 5: Solve for x
    x = 87,330.59/305.59
  6. Step 6: Final answer
    x = 285.78

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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.