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Finding the Fourth Proportional to 386.48, 578.90 and 321.68

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Solution

The fourth proportional to 386.48, 578.90 and 321.68 is: 481.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.48 : 578.90 = 321.68 : x
  2. Step 2: Convert to fraction form
    386.48/578.90 = 321.68/x
  3. Step 3: Cross multiply
    386.48x = 578.90 × 321.68
  4. Step 4: Simplify right side
    386.48x = 186,220.55
  5. Step 5: Solve for x
    x = 186,220.55/386.48
  6. Step 6: Final answer
    x = 481.84

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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.