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Finding the Fourth Proportional to 621.91, 858.09 and 400.92

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Solution

The fourth proportional to 621.91, 858.09 and 400.92 is: 553.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.91 : 858.09 = 400.92 : x
  2. Step 2: Convert to fraction form
    621.91/858.09 = 400.92/x
  3. Step 3: Cross multiply
    621.91x = 858.09 × 400.92
  4. Step 4: Simplify right side
    621.91x = 344,025.44
  5. Step 5: Solve for x
    x = 344,025.44/621.91
  6. Step 6: Final answer
    x = 553.18

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1.5x scale

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.