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Finding the Fourth Proportional to 390.46, 539.04 and 285.79

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Solution

The fourth proportional to 390.46, 539.04 and 285.79 is: 394.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.46 : 539.04 = 285.79 : x
  2. Step 2: Convert to fraction form
    390.46/539.04 = 285.79/x
  3. Step 3: Cross multiply
    390.46x = 539.04 × 285.79
  4. Step 4: Simplify right side
    390.46x = 154,052.24
  5. Step 5: Solve for x
    x = 154,052.24/390.46
  6. Step 6: Final answer
    x = 394.54

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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.