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Finding the Fourth Proportional to 689.66, 952.05 and 394.87

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Solution

The fourth proportional to 689.66, 952.05 and 394.87 is: 545.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    689.66 : 952.05 = 394.87 : x
  2. Step 2: Convert to fraction form
    689.66/952.05 = 394.87/x
  3. Step 3: Cross multiply
    689.66x = 952.05 × 394.87
  4. Step 4: Simplify right side
    689.66x = 375,931.22
  5. Step 5: Solve for x
    x = 375,931.22/689.66
  6. Step 6: Final answer
    x = 545.10

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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.