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Finding the Fourth Proportional to 427.22, 639.42 and 303.20

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Solution

The fourth proportional to 427.22, 639.42 and 303.20 is: 453.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.22 : 639.42 = 303.20 : x
  2. Step 2: Convert to fraction form
    427.22/639.42 = 303.20/x
  3. Step 3: Cross multiply
    427.22x = 639.42 × 303.20
  4. Step 4: Simplify right side
    427.22x = 193,872.14
  5. Step 5: Solve for x
    x = 193,872.14/427.22
  6. Step 6: Final answer
    x = 453.80

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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.