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Finding the Fourth Proportional to 380.31, 570.47 and 91.75

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Solution

The fourth proportional to 380.31, 570.47 and 91.75 is: 137.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    380.31 : 570.47 = 91.75 : x
  2. Step 2: Convert to fraction form
    380.31/570.47 = 91.75/x
  3. Step 3: Cross multiply
    380.31x = 570.47 × 91.75
  4. Step 4: Simplify right side
    380.31x = 52,340.62
  5. Step 5: Solve for x
    x = 52,340.62/380.31
  6. Step 6: Final answer
    x = 137.63

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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.