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Finding the Fourth Proportional to 386.55, 579.38 and 213.02

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Solution

The fourth proportional to 386.55, 579.38 and 213.02 is: 319.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.55 : 579.38 = 213.02 : x
  2. Step 2: Convert to fraction form
    386.55/579.38 = 213.02/x
  3. Step 3: Cross multiply
    386.55x = 579.38 × 213.02
  4. Step 4: Simplify right side
    386.55x = 123,415.57
  5. Step 5: Solve for x
    x = 123,415.57/386.55
  6. Step 6: Final answer
    x = 319.27

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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.