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Finding the Fourth Proportional to 278.56, 387.08 and 275.56

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Solution

The fourth proportional to 278.56, 387.08 and 275.56 is: 382.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.56 : 387.08 = 275.56 : x
  2. Step 2: Convert to fraction form
    278.56/387.08 = 275.56/x
  3. Step 3: Cross multiply
    278.56x = 387.08 × 275.56
  4. Step 4: Simplify right side
    278.56x = 106,663.76
  5. Step 5: Solve for x
    x = 106,663.76/278.56
  6. Step 6: Final answer
    x = 382.91

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.