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Finding the Fourth Proportional to 386.31, 529.29 and 380.91

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Solution

The fourth proportional to 386.31, 529.29 and 380.91 is: 521.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.31 : 529.29 = 380.91 : x
  2. Step 2: Convert to fraction form
    386.31/529.29 = 380.91/x
  3. Step 3: Cross multiply
    386.31x = 529.29 × 380.91
  4. Step 4: Simplify right side
    386.31x = 201,611.85
  5. Step 5: Solve for x
    x = 201,611.85/386.31
  6. Step 6: Final answer
    x = 521.89

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.