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Finding the Fourth Proportional to 427.68, 641.49 and 208.37

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Solution

The fourth proportional to 427.68, 641.49 and 208.37 is: 312.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.68 : 641.49 = 208.37 : x
  2. Step 2: Convert to fraction form
    427.68/641.49 = 208.37/x
  3. Step 3: Cross multiply
    427.68x = 641.49 × 208.37
  4. Step 4: Simplify right side
    427.68x = 133,668.09
  5. Step 5: Solve for x
    x = 133,668.09/427.68
  6. Step 6: Final answer
    x = 312.54

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.