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Finding the Fourth Proportional to 478.20, 660.01 and 279.05

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Solution

The fourth proportional to 478.20, 660.01 and 279.05 is: 385.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.20 : 660.01 = 279.05 : x
  2. Step 2: Convert to fraction form
    478.20/660.01 = 279.05/x
  3. Step 3: Cross multiply
    478.20x = 660.01 × 279.05
  4. Step 4: Simplify right side
    478.20x = 184,176.39
  5. Step 5: Solve for x
    x = 184,176.39/478.20
  6. Step 6: Final answer
    x = 385.15

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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.