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Finding the Fourth Proportional to 278.49, 384.08 and 208.71

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Solution

The fourth proportional to 278.49, 384.08 and 208.71 is: 287.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.49 : 384.08 = 208.71 : x
  2. Step 2: Convert to fraction form
    278.49/384.08 = 208.71/x
  3. Step 3: Cross multiply
    278.49x = 384.08 × 208.71
  4. Step 4: Simplify right side
    278.49x = 80,160.29
  5. Step 5: Solve for x
    x = 80,160.29/278.49
  6. Step 6: Final answer
    x = 287.84

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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.