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Finding the Fourth Proportional to 515.71, 711.49 and 397.72

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Solution

The fourth proportional to 515.71, 711.49 and 397.72 is: 548.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    515.71 : 711.49 = 397.72 : x
  2. Step 2: Convert to fraction form
    515.71/711.49 = 397.72/x
  3. Step 3: Cross multiply
    515.71x = 711.49 × 397.72
  4. Step 4: Simplify right side
    515.71x = 282,973.80
  5. Step 5: Solve for x
    x = 282,973.80/515.71
  6. Step 6: Final answer
    x = 548.71

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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.