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Finding the Fourth Proportional to 205.80, 308.74 and 90.26

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Solution

The fourth proportional to 205.80, 308.74 and 90.26 is: 135.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.80 : 308.74 = 90.26 : x
  2. Step 2: Convert to fraction form
    205.80/308.74 = 90.26/x
  3. Step 3: Cross multiply
    205.80x = 308.74 × 90.26
  4. Step 4: Simplify right side
    205.80x = 27,866.87
  5. Step 5: Solve for x
    x = 27,866.87/205.80
  6. Step 6: Final answer
    x = 135.41

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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.