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Finding the Fourth Proportional to 386.80, 579.28 and 324.80

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Solution

The fourth proportional to 386.80, 579.28 and 324.80 is: 486.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.80 : 579.28 = 324.80 : x
  2. Step 2: Convert to fraction form
    386.80/579.28 = 324.80/x
  3. Step 3: Cross multiply
    386.80x = 579.28 × 324.80
  4. Step 4: Simplify right side
    386.80x = 188,150.14
  5. Step 5: Solve for x
    x = 188,150.14/386.80
  6. Step 6: Final answer
    x = 486.43

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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.