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Finding the Fourth Proportional to 387.90, 535.22 and 219.86

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Solution

The fourth proportional to 387.90, 535.22 and 219.86 is: 303.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.90 : 535.22 = 219.86 : x
  2. Step 2: Convert to fraction form
    387.90/535.22 = 219.86/x
  3. Step 3: Cross multiply
    387.90x = 535.22 × 219.86
  4. Step 4: Simplify right side
    387.90x = 117,673.47
  5. Step 5: Solve for x
    x = 117,673.47/387.90
  6. Step 6: Final answer
    x = 303.36

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.