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Finding the Fourth Proportional to 390.50, 539.61 and 371.52

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Solution

The fourth proportional to 390.50, 539.61 and 371.52 is: 513.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.50 : 539.61 = 371.52 : x
  2. Step 2: Convert to fraction form
    390.50/539.61 = 371.52/x
  3. Step 3: Cross multiply
    390.50x = 539.61 × 371.52
  4. Step 4: Simplify right side
    390.50x = 200,475.91
  5. Step 5: Solve for x
    x = 200,475.91/390.50
  6. Step 6: Final answer
    x = 513.38

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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.