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Finding the Fourth Proportional to 278.86, 384.78 and 185.78

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Solution

The fourth proportional to 278.86, 384.78 and 185.78 is: 256.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.86 : 384.78 = 185.78 : x
  2. Step 2: Convert to fraction form
    278.86/384.78 = 185.78/x
  3. Step 3: Cross multiply
    278.86x = 384.78 × 185.78
  4. Step 4: Simplify right side
    278.86x = 71,484.43
  5. Step 5: Solve for x
    x = 71,484.43/278.86
  6. Step 6: Final answer
    x = 256.35

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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.