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Finding the Fourth Proportional to 623.87, 861.63 and 485.65

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Solution

The fourth proportional to 623.87, 861.63 and 485.65 is: 670.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    623.87 : 861.63 = 485.65 : x
  2. Step 2: Convert to fraction form
    623.87/861.63 = 485.65/x
  3. Step 3: Cross multiply
    623.87x = 861.63 × 485.65
  4. Step 4: Simplify right side
    623.87x = 418,446.30
  5. Step 5: Solve for x
    x = 418,446.30/623.87
  6. Step 6: Final answer
    x = 670.73

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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.