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Finding the Fourth Proportional to 309.85, 427.38 and 185.42

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Solution

The fourth proportional to 309.85, 427.38 and 185.42 is: 255.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.85 : 427.38 = 185.42 : x
  2. Step 2: Convert to fraction form
    309.85/427.38 = 185.42/x
  3. Step 3: Cross multiply
    309.85x = 427.38 × 185.42
  4. Step 4: Simplify right side
    309.85x = 79,245.87
  5. Step 5: Solve for x
    x = 79,245.87/309.85
  6. Step 6: Final answer
    x = 255.76

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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.