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Finding the Fourth Proportional to 621.30, 857.22 and 359.40

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Solution

The fourth proportional to 621.30, 857.22 and 359.40 is: 495.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.30 : 857.22 = 359.40 : x
  2. Step 2: Convert to fraction form
    621.30/857.22 = 359.40/x
  3. Step 3: Cross multiply
    621.30x = 857.22 × 359.40
  4. Step 4: Simplify right side
    621.30x = 308,084.87
  5. Step 5: Solve for x
    x = 308,084.87/621.30
  6. Step 6: Final answer
    x = 495.87

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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.