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Finding the Fourth Proportional to 278.21, 384.28 and 208.60

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Solution

The fourth proportional to 278.21, 384.28 and 208.60 is: 288.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.21 : 384.28 = 208.60 : x
  2. Step 2: Convert to fraction form
    278.21/384.28 = 208.60/x
  3. Step 3: Cross multiply
    278.21x = 384.28 × 208.60
  4. Step 4: Simplify right side
    278.21x = 80,159.33
  5. Step 5: Solve for x
    x = 80,159.33/278.21
  6. Step 6: Final answer
    x = 288.12

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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.