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Finding the Fourth Proportional to 621.38, 858.43 and 409.19

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Solution

The fourth proportional to 621.38, 858.43 and 409.19 is: 565.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.38 : 858.43 = 409.19 : x
  2. Step 2: Convert to fraction form
    621.38/858.43 = 409.19/x
  3. Step 3: Cross multiply
    621.38x = 858.43 × 409.19
  4. Step 4: Simplify right side
    621.38x = 351,262.09
  5. Step 5: Solve for x
    x = 351,262.09/621.38
  6. Step 6: Final answer
    x = 565.30

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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.