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Finding the Fourth Proportional to 680.67, 939.30 and 381.90

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Solution

The fourth proportional to 680.67, 939.30 and 381.90 is: 527.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.67 : 939.30 = 381.90 : x
  2. Step 2: Convert to fraction form
    680.67/939.30 = 381.90/x
  3. Step 3: Cross multiply
    680.67x = 939.30 × 381.90
  4. Step 4: Simplify right side
    680.67x = 358,715.15
  5. Step 5: Solve for x
    x = 358,715.15/680.67
  6. Step 6: Final answer
    x = 527.00

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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.