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Finding the Fourth Proportional to 690.20, 952.47 and 379.70

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Solution

The fourth proportional to 690.20, 952.47 and 379.70 is: 523.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.20 : 952.47 = 379.70 : x
  2. Step 2: Convert to fraction form
    690.20/952.47 = 379.70/x
  3. Step 3: Cross multiply
    690.20x = 952.47 × 379.70
  4. Step 4: Simplify right side
    690.20x = 361,648.10
  5. Step 5: Solve for x
    x = 361,648.10/690.20
  6. Step 6: Final answer
    x = 523.98

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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.