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Finding the Fourth Proportional to 308.85, 425.86 and 286.98

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Solution

The fourth proportional to 308.85, 425.86 and 286.98 is: 395.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.85 : 425.86 = 286.98 : x
  2. Step 2: Convert to fraction form
    308.85/425.86 = 286.98/x
  3. Step 3: Cross multiply
    308.85x = 425.86 × 286.98
  4. Step 4: Simplify right side
    308.85x = 122,213.30
  5. Step 5: Solve for x
    x = 122,213.30/308.85
  6. Step 6: Final answer
    x = 395.70

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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.