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Finding the Fourth Proportional to 386.37, 578.74 and 321.21

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Solution

The fourth proportional to 386.37, 578.74 and 321.21 is: 481.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.37 : 578.74 = 321.21 : x
  2. Step 2: Convert to fraction form
    386.37/578.74 = 321.21/x
  3. Step 3: Cross multiply
    386.37x = 578.74 × 321.21
  4. Step 4: Simplify right side
    386.37x = 185,897.08
  5. Step 5: Solve for x
    x = 185,897.08/386.37
  6. Step 6: Final answer
    x = 481.14

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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.