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Finding the Fourth Proportional to 428.41, 642.31 and 181.63

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Solution

The fourth proportional to 428.41, 642.31 and 181.63 is: 272.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.41 : 642.31 = 181.63 : x
  2. Step 2: Convert to fraction form
    428.41/642.31 = 181.63/x
  3. Step 3: Cross multiply
    428.41x = 642.31 × 181.63
  4. Step 4: Simplify right side
    428.41x = 116,662.77
  5. Step 5: Solve for x
    x = 116,662.77/428.41
  6. Step 6: Final answer
    x = 272.32

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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.