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Finding the Third Proportional to 390.50 and 559

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Solution

The third proportional to 390.50 and 559 is: 800.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    390.50 : 559 = 559 : x
  2. Step 2: Convert to fraction form
    390.50/559 = 559/x
  3. Step 3: Cross multiply
    390.50x = 559 × 559
  4. Step 4: Simplify right side
    390.50x = 312,481
  5. Step 5: Solve for x
    x = 312,481/390.50
  6. Step 6: Final answer
    x = 800.21

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Why These Related Problems?

These problems maintain the same ratio (1.43) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.