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Finding the Fourth Proportional to 479.18, 662.20 and 390.48

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Solution

The fourth proportional to 479.18, 662.20 and 390.48 is: 539.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.18 : 662.20 = 390.48 : x
  2. Step 2: Convert to fraction form
    479.18/662.20 = 390.48/x
  3. Step 3: Cross multiply
    479.18x = 662.20 × 390.48
  4. Step 4: Simplify right side
    479.18x = 258,575.86
  5. Step 5: Solve for x
    x = 258,575.86/479.18
  6. Step 6: Final answer
    x = 539.62

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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.