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Finding the Fourth Proportional to 390.70, 539.04 and 297.55

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Solution

The fourth proportional to 390.70, 539.04 and 297.55 is: 410.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.70 : 539.04 = 297.55 : x
  2. Step 2: Convert to fraction form
    390.70/539.04 = 297.55/x
  3. Step 3: Cross multiply
    390.70x = 539.04 × 297.55
  4. Step 4: Simplify right side
    390.70x = 160,391.35
  5. Step 5: Solve for x
    x = 160,391.35/390.70
  6. Step 6: Final answer
    x = 410.52

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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.