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Finding the Fourth Proportional to 278.40, 417.12 and 263.20

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Solution

The fourth proportional to 278.40, 417.12 and 263.20 is: 394.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.40 : 417.12 = 263.20 : x
  2. Step 2: Convert to fraction form
    278.40/417.12 = 263.20/x
  3. Step 3: Cross multiply
    278.40x = 417.12 × 263.20
  4. Step 4: Simplify right side
    278.40x = 109,785.98
  5. Step 5: Solve for x
    x = 109,785.98/278.40
  6. Step 6: Final answer
    x = 394.35

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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.