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Finding the Fourth Proportional to 479.20, 661.45 and 280.07

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Solution

The fourth proportional to 479.20, 661.45 and 280.07 is: 386.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.20 : 661.45 = 280.07 : x
  2. Step 2: Convert to fraction form
    479.20/661.45 = 280.07/x
  3. Step 3: Cross multiply
    479.20x = 661.45 × 280.07
  4. Step 4: Simplify right side
    479.20x = 185,255.02
  5. Step 5: Solve for x
    x = 185,255.02/479.20
  6. Step 6: Final answer
    x = 386.59

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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.