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Finding the Fourth Proportional to 321.31, 481.90 and 90.22

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Solution

The fourth proportional to 321.31, 481.90 and 90.22 is: 135.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.31 : 481.90 = 90.22 : x
  2. Step 2: Convert to fraction form
    321.31/481.90 = 90.22/x
  3. Step 3: Cross multiply
    321.31x = 481.90 × 90.22
  4. Step 4: Simplify right side
    321.31x = 43,477.02
  5. Step 5: Solve for x
    x = 43,477.02/321.31
  6. Step 6: Final answer
    x = 135.31

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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.