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Finding the Fourth Proportional to 215.09, 319.87 and 208.26

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Solution

The fourth proportional to 215.09, 319.87 and 208.26 is: 309.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.09 : 319.87 = 208.26 : x
  2. Step 2: Convert to fraction form
    215.09/319.87 = 208.26/x
  3. Step 3: Cross multiply
    215.09x = 319.87 × 208.26
  4. Step 4: Simplify right side
    215.09x = 66,616.13
  5. Step 5: Solve for x
    x = 66,616.13/215.09
  6. Step 6: Final answer
    x = 309.71

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.