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Finding the Fourth Proportional to 689.93, 952.05 and 391.09

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Solution

The fourth proportional to 689.93, 952.05 and 391.09 is: 539.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.93 : 952.05 = 391.09 : x
  2. Step 2: Convert to fraction form
    689.93/952.05 = 391.09/x
  3. Step 3: Cross multiply
    689.93x = 952.05 × 391.09
  4. Step 4: Simplify right side
    689.93x = 372,337.23
  5. Step 5: Solve for x
    x = 372,337.23/689.93
  6. Step 6: Final answer
    x = 539.67

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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.