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Finding the Fourth Proportional to 427.85, 641.91 and 254.72

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Solution

The fourth proportional to 427.85, 641.91 and 254.72 is: 382.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.85 : 641.91 = 254.72 : x
  2. Step 2: Convert to fraction form
    427.85/641.91 = 254.72/x
  3. Step 3: Cross multiply
    427.85x = 641.91 × 254.72
  4. Step 4: Simplify right side
    427.85x = 163,504.11
  5. Step 5: Solve for x
    x = 163,504.11/427.85
  6. Step 6: Final answer
    x = 382.15

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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.