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Finding the Fourth Proportional to 278.47, 383.86 and 208.42

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Solution

The fourth proportional to 278.47, 383.86 and 208.42 is: 287.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.47 : 383.86 = 208.42 : x
  2. Step 2: Convert to fraction form
    278.47/383.86 = 208.42/x
  3. Step 3: Cross multiply
    278.47x = 383.86 × 208.42
  4. Step 4: Simplify right side
    278.47x = 80,005.32
  5. Step 5: Solve for x
    x = 80,005.32/278.47
  6. Step 6: Final answer
    x = 287.30

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.