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Finding the Fourth Proportional to 278.80, 384.78 and 212.29

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Solution

The fourth proportional to 278.80, 384.78 and 212.29 is: 292.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.80 : 384.78 = 212.29 : x
  2. Step 2: Convert to fraction form
    278.80/384.78 = 212.29/x
  3. Step 3: Cross multiply
    278.80x = 384.78 × 212.29
  4. Step 4: Simplify right side
    278.80x = 81,685.02
  5. Step 5: Solve for x
    x = 81,685.02/278.80
  6. Step 6: Final answer
    x = 292.99

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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.