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Finding the Fourth Proportional to 386.78, 579.56 and 181.31

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Solution

The fourth proportional to 386.78, 579.56 and 181.31 is: 271.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.78 : 579.56 = 181.31 : x
  2. Step 2: Convert to fraction form
    386.78/579.56 = 181.31/x
  3. Step 3: Cross multiply
    386.78x = 579.56 × 181.31
  4. Step 4: Simplify right side
    386.78x = 105,076.22
  5. Step 5: Solve for x
    x = 105,076.22/386.78
  6. Step 6: Final answer
    x = 271.67

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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.