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Finding the Fourth Proportional to 618.34, 853.02 and 397.21

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Solution

The fourth proportional to 618.34, 853.02 and 397.21 is: 547.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.34 : 853.02 = 397.21 : x
  2. Step 2: Convert to fraction form
    618.34/853.02 = 397.21/x
  3. Step 3: Cross multiply
    618.34x = 853.02 × 397.21
  4. Step 4: Simplify right side
    618.34x = 338,828.07
  5. Step 5: Solve for x
    x = 338,828.07/618.34
  6. Step 6: Final answer
    x = 547.96

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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.