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Finding the Fourth Proportional to 278.64, 417.56 and 258.39

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Solution

The fourth proportional to 278.64, 417.56 and 258.39 is: 387.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.64 : 417.56 = 258.39 : x
  2. Step 2: Convert to fraction form
    278.64/417.56 = 258.39/x
  3. Step 3: Cross multiply
    278.64x = 417.56 × 258.39
  4. Step 4: Simplify right side
    278.64x = 107,892.04
  5. Step 5: Solve for x
    x = 107,892.04/278.64
  6. Step 6: Final answer
    x = 387.21

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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.