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Finding the Fourth Proportional to 478.86, 660.80 and 279.66

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Solution

The fourth proportional to 478.86, 660.80 and 279.66 is: 385.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.86 : 660.80 = 279.66 : x
  2. Step 2: Convert to fraction form
    478.86/660.80 = 279.66/x
  3. Step 3: Cross multiply
    478.86x = 660.80 × 279.66
  4. Step 4: Simplify right side
    478.86x = 184,797.93
  5. Step 5: Solve for x
    x = 184,797.93/478.86
  6. Step 6: Final answer
    x = 385.91

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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.