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Finding the Fourth Proportional to 479.27, 661.31 and 280.11

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Solution

The fourth proportional to 479.27, 661.31 and 280.11 is: 386.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.27 : 661.31 = 280.11 : x
  2. Step 2: Convert to fraction form
    479.27/661.31 = 280.11/x
  3. Step 3: Cross multiply
    479.27x = 661.31 × 280.11
  4. Step 4: Simplify right side
    479.27x = 185,238.14
  5. Step 5: Solve for x
    x = 185,238.14/479.27
  6. Step 6: Final answer
    x = 386.50

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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.