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Finding the Fourth Proportional to 309.65, 426.98 and 209.94

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Solution

The fourth proportional to 309.65, 426.98 and 209.94 is: 289.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.65 : 426.98 = 209.94 : x
  2. Step 2: Convert to fraction form
    309.65/426.98 = 209.94/x
  3. Step 3: Cross multiply
    309.65x = 426.98 × 209.94
  4. Step 4: Simplify right side
    309.65x = 89,639.13
  5. Step 5: Solve for x
    x = 89,639.13/309.65
  6. Step 6: Final answer
    x = 289.49

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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.