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Finding the Fourth Proportional to 664.42, 996.29 and 420.42

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Solution

The fourth proportional to 664.42, 996.29 and 420.42 is: 630.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.42 : 996.29 = 420.42 : x
  2. Step 2: Convert to fraction form
    664.42/996.29 = 420.42/x
  3. Step 3: Cross multiply
    664.42x = 996.29 × 420.42
  4. Step 4: Simplify right side
    664.42x = 418,860.24
  5. Step 5: Solve for x
    x = 418,860.24/664.42
  6. Step 6: Final answer
    x = 630.41

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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.