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Finding the Fourth Proportional to 478.79, 660.81 and 279.65

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Solution

The fourth proportional to 478.79, 660.81 and 279.65 is: 385.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    478.79 : 660.81 = 279.65 : x
  2. Step 2: Convert to fraction form
    478.79/660.81 = 279.65/x
  3. Step 3: Cross multiply
    478.79x = 660.81 × 279.65
  4. Step 4: Simplify right side
    478.79x = 184,790.81
  5. Step 5: Solve for x
    x = 184,790.81/478.79
  6. Step 6: Final answer
    x = 385.96

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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.