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Finding the Fourth Proportional to 321.92, 482.86 and 90.81

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Solution

The fourth proportional to 321.92, 482.86 and 90.81 is: 136.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.92 : 482.86 = 90.81 : x
  2. Step 2: Convert to fraction form
    321.92/482.86 = 90.81/x
  3. Step 3: Cross multiply
    321.92x = 482.86 × 90.81
  4. Step 4: Simplify right side
    321.92x = 43,848.12
  5. Step 5: Solve for x
    x = 43,848.12/321.92
  6. Step 6: Final answer
    x = 136.21

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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.