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Finding the Fourth Proportional to 309.40, 426.78 and 185.08

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Solution

The fourth proportional to 309.40, 426.78 and 185.08 is: 255.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.40 : 426.78 = 185.08 : x
  2. Step 2: Convert to fraction form
    309.40/426.78 = 185.08/x
  3. Step 3: Cross multiply
    309.40x = 426.78 × 185.08
  4. Step 4: Simplify right side
    309.40x = 78,988.44
  5. Step 5: Solve for x
    x = 78,988.44/309.40
  6. Step 6: Final answer
    x = 255.30

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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.