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Finding the Fourth Proportional to 420.69, 630.68 and 204.42

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Solution

The fourth proportional to 420.69, 630.68 and 204.42 is: 306.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.69 : 630.68 = 204.42 : x
  2. Step 2: Convert to fraction form
    420.69/630.68 = 204.42/x
  3. Step 3: Cross multiply
    420.69x = 630.68 × 204.42
  4. Step 4: Simplify right side
    420.69x = 128,922.58
  5. Step 5: Solve for x
    x = 128,922.58/420.69
  6. Step 6: Final answer
    x = 306.46

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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.