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Finding the Fourth Proportional to 304.86, 420.78 and 180.55

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Solution

The fourth proportional to 304.86, 420.78 and 180.55 is: 249.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    304.86 : 420.78 = 180.55 : x
  2. Step 2: Convert to fraction form
    304.86/420.78 = 180.55/x
  3. Step 3: Cross multiply
    304.86x = 420.78 × 180.55
  4. Step 4: Simplify right side
    304.86x = 75,972.02
  5. Step 5: Solve for x
    x = 75,972.02/304.86
  6. Step 6: Final answer
    x = 249.21

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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.