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Finding the Fourth Proportional to 621.29, 857.39 and 385.23

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Solution

The fourth proportional to 621.29, 857.39 and 385.23 is: 531.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.29 : 857.39 = 385.23 : x
  2. Step 2: Convert to fraction form
    621.29/857.39 = 385.23/x
  3. Step 3: Cross multiply
    621.29x = 857.39 × 385.23
  4. Step 4: Simplify right side
    621.29x = 330,290.42
  5. Step 5: Solve for x
    x = 330,290.42/621.29
  6. Step 6: Final answer
    x = 531.62

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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.