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Finding the Fourth Proportional to 205.74, 308.66 and 90.25

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Solution

The fourth proportional to 205.74, 308.66 and 90.25 is: 135.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    205.74 : 308.66 = 90.25 : x
  2. Step 2: Convert to fraction form
    205.74/308.66 = 90.25/x
  3. Step 3: Cross multiply
    205.74x = 308.66 × 90.25
  4. Step 4: Simplify right side
    205.74x = 27,855.34
  5. Step 5: Solve for x
    x = 27,855.34/205.74
  6. Step 6: Final answer
    x = 135.39

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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.