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Finding the Fourth Proportional to 621.85, 858.18 and 342.09

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Solution

The fourth proportional to 621.85, 858.18 and 342.09 is: 472.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.85 : 858.18 = 342.09 : x
  2. Step 2: Convert to fraction form
    621.85/858.18 = 342.09/x
  3. Step 3: Cross multiply
    621.85x = 858.18 × 342.09
  4. Step 4: Simplify right side
    621.85x = 293,574.80
  5. Step 5: Solve for x
    x = 293,574.80/621.85
  6. Step 6: Final answer
    x = 472.10

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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.