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Finding the Fourth Proportional to 278.30, 415.16 and 258.66

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Solution

The fourth proportional to 278.30, 415.16 and 258.66 is: 385.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.30 : 415.16 = 258.66 : x
  2. Step 2: Convert to fraction form
    278.30/415.16 = 258.66/x
  3. Step 3: Cross multiply
    278.30x = 415.16 × 258.66
  4. Step 4: Simplify right side
    278.30x = 107,384.96
  5. Step 5: Solve for x
    x = 107,384.96/278.30
  6. Step 6: Final answer
    x = 385.86

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.