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Finding the Fourth Proportional to 305.85, 421.95 and 207.69

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Solution

The fourth proportional to 305.85, 421.95 and 207.69 is: 286.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.85 : 421.95 = 207.69 : x
  2. Step 2: Convert to fraction form
    305.85/421.95 = 207.69/x
  3. Step 3: Cross multiply
    305.85x = 421.95 × 207.69
  4. Step 4: Simplify right side
    305.85x = 87,634.80
  5. Step 5: Solve for x
    x = 87,634.80/305.85
  6. Step 6: Final answer
    x = 286.53

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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.