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Finding the Fourth Proportional to 278.10, 417.55 and 217.30

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Solution

The fourth proportional to 278.10, 417.55 and 217.30 is: 326.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.10 : 417.55 = 217.30 : x
  2. Step 2: Convert to fraction form
    278.10/417.55 = 217.30/x
  3. Step 3: Cross multiply
    278.10x = 417.55 × 217.30
  4. Step 4: Simplify right side
    278.10x = 90,733.62
  5. Step 5: Solve for x
    x = 90,733.62/278.10
  6. Step 6: Final answer
    x = 326.26

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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.