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Finding the Fourth Proportional to 830.38, 1,243.26 and 418.65

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Solution

The fourth proportional to 830.38, 1,243.26 and 418.65 is: 626.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    830.38 : 1,243.26 = 418.65 : x
  2. Step 2: Convert to fraction form
    830.38/1,243.26 = 418.65/x
  3. Step 3: Cross multiply
    830.38x = 1,243.26 × 418.65
  4. Step 4: Simplify right side
    830.38x = 520,487.80
  5. Step 5: Solve for x
    x = 520,487.80/830.38
  6. Step 6: Final answer
    x = 626.81

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.