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Finding the Fourth Proportional to 486.78, 729.75 and 278.50

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Solution

The fourth proportional to 486.78, 729.75 and 278.50 is: 417.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.78 : 729.75 = 278.50 : x
  2. Step 2: Convert to fraction form
    486.78/729.75 = 278.50/x
  3. Step 3: Cross multiply
    486.78x = 729.75 × 278.50
  4. Step 4: Simplify right side
    486.78x = 203,235.38
  5. Step 5: Solve for x
    x = 203,235.38/486.78
  6. Step 6: Final answer
    x = 417.51

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.