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Finding the Fourth Proportional to 621.70, 931.20 and 540.70

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Solution

The fourth proportional to 621.70, 931.20 and 540.70 is: 809.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.70 : 931.20 = 540.70 : x
  2. Step 2: Convert to fraction form
    621.70/931.20 = 540.70/x
  3. Step 3: Cross multiply
    621.70x = 931.20 × 540.70
  4. Step 4: Simplify right side
    621.70x = 503,499.84
  5. Step 5: Solve for x
    x = 503,499.84/621.70
  6. Step 6: Final answer
    x = 809.88

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.