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Finding the Fourth Proportional to 391.66, 540.47 and 217.01

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Solution

The fourth proportional to 391.66, 540.47 and 217.01 is: 299.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.66 : 540.47 = 217.01 : x
  2. Step 2: Convert to fraction form
    391.66/540.47 = 217.01/x
  3. Step 3: Cross multiply
    391.66x = 540.47 × 217.01
  4. Step 4: Simplify right side
    391.66x = 117,289.29
  5. Step 5: Solve for x
    x = 117,289.29/391.66
  6. Step 6: Final answer
    x = 299.47

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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.