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Finding the Fourth Proportional to 304.80, 420.55 and 206.65

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Solution

The fourth proportional to 304.80, 420.55 and 206.65 is: 285.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.80 : 420.55 = 206.65 : x
  2. Step 2: Convert to fraction form
    304.80/420.55 = 206.65/x
  3. Step 3: Cross multiply
    304.80x = 420.55 × 206.65
  4. Step 4: Simplify right side
    304.80x = 86,906.66
  5. Step 5: Solve for x
    x = 86,906.66/304.80
  6. Step 6: Final answer
    x = 285.13

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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.