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Finding the Fourth Proportional to 618.80, 853.80 and 385.76

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Solution

The fourth proportional to 618.80, 853.80 and 385.76 is: 532.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.80 : 853.80 = 385.76 : x
  2. Step 2: Convert to fraction form
    618.80/853.80 = 385.76/x
  3. Step 3: Cross multiply
    618.80x = 853.80 × 385.76
  4. Step 4: Simplify right side
    618.80x = 329,361.89
  5. Step 5: Solve for x
    x = 329,361.89/618.80
  6. Step 6: Final answer
    x = 532.26

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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.