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Finding the Fourth Proportional to 308.65, 426.38 and 215.65

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Solution

The fourth proportional to 308.65, 426.38 and 215.65 is: 297.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    308.65 : 426.38 = 215.65 : x
  2. Step 2: Convert to fraction form
    308.65/426.38 = 215.65/x
  3. Step 3: Cross multiply
    308.65x = 426.38 × 215.65
  4. Step 4: Simplify right side
    308.65x = 91,948.85
  5. Step 5: Solve for x
    x = 91,948.85/308.65
  6. Step 6: Final answer
    x = 297.91

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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.