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Finding the Fourth Proportional to 305.00, 420.75 and 206.79

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Solution

The fourth proportional to 305.00, 420.75 and 206.79 is: 285.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.00 : 420.75 = 206.79 : x
  2. Step 2: Convert to fraction form
    305.00/420.75 = 206.79/x
  3. Step 3: Cross multiply
    305.00x = 420.75 × 206.79
  4. Step 4: Simplify right side
    305.00x = 87,006.89
  5. Step 5: Solve for x
    x = 87,006.89/305.00
  6. Step 6: Final answer
    x = 285.27

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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.