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Finding the Fourth Proportional to 618.36, 853.70 and 385.80

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Solution

The fourth proportional to 618.36, 853.70 and 385.80 is: 532.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.36 : 853.70 = 385.80 : x
  2. Step 2: Convert to fraction form
    618.36/853.70 = 385.80/x
  3. Step 3: Cross multiply
    618.36x = 853.70 × 385.80
  4. Step 4: Simplify right side
    618.36x = 329,357.46
  5. Step 5: Solve for x
    x = 329,357.46/618.36
  6. Step 6: Final answer
    x = 532.63

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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.