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Finding the Fourth Proportional to 309.56, 426.06 and 287.18

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Solution

The fourth proportional to 309.56, 426.06 and 287.18 is: 395.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.56 : 426.06 = 287.18 : x
  2. Step 2: Convert to fraction form
    309.56/426.06 = 287.18/x
  3. Step 3: Cross multiply
    309.56x = 426.06 × 287.18
  4. Step 4: Simplify right side
    309.56x = 122,355.38
  5. Step 5: Solve for x
    x = 122,355.38/309.56
  6. Step 6: Final answer
    x = 395.26

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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.