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Finding the Fourth Proportional to 278.28, 415.38 and 258.26

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Solution

The fourth proportional to 278.28, 415.38 and 258.26 is: 385.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.28 : 415.38 = 258.26 : x
  2. Step 2: Convert to fraction form
    278.28/415.38 = 258.26/x
  3. Step 3: Cross multiply
    278.28x = 415.38 × 258.26
  4. Step 4: Simplify right side
    278.28x = 107,276.04
  5. Step 5: Solve for x
    x = 107,276.04/278.28
  6. Step 6: Final answer
    x = 385.50

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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.