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Finding the Fourth Proportional to 305.00, 420.87 and 180.66

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Solution

The fourth proportional to 305.00, 420.87 and 180.66 is: 249.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.00 : 420.87 = 180.66 : x
  2. Step 2: Convert to fraction form
    305.00/420.87 = 180.66/x
  3. Step 3: Cross multiply
    305.00x = 420.87 × 180.66
  4. Step 4: Simplify right side
    305.00x = 76,034.37
  5. Step 5: Solve for x
    x = 76,034.37/305.00
  6. Step 6: Final answer
    x = 249.30

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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.