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Finding the Fourth Proportional to 428.82, 642.58 and 263.86

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Solution

The fourth proportional to 428.82, 642.58 and 263.86 is: 395.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.82 : 642.58 = 263.86 : x
  2. Step 2: Convert to fraction form
    428.82/642.58 = 263.86/x
  3. Step 3: Cross multiply
    428.82x = 642.58 × 263.86
  4. Step 4: Simplify right side
    428.82x = 169,551.16
  5. Step 5: Solve for x
    x = 169,551.16/428.82
  6. Step 6: Final answer
    x = 395.39

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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.