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Finding the Fourth Proportional to 201.21, 301.80 and 71.20

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Solution

The fourth proportional to 201.21, 301.80 and 71.20 is: 106.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    201.21 : 301.80 = 71.20 : x
  2. Step 2: Convert to fraction form
    201.21/301.80 = 71.20/x
  3. Step 3: Cross multiply
    201.21x = 301.80 × 71.20
  4. Step 4: Simplify right side
    201.21x = 21,488.16
  5. Step 5: Solve for x
    x = 21,488.16/201.21
  6. Step 6: Final answer
    x = 106.79

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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.