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Finding the Fourth Proportional to 429.07, 643.99 and 223.78

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Solution

The fourth proportional to 429.07, 643.99 and 223.78 is: 335.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    429.07 : 643.99 = 223.78 : x
  2. Step 2: Convert to fraction form
    429.07/643.99 = 223.78/x
  3. Step 3: Cross multiply
    429.07x = 643.99 × 223.78
  4. Step 4: Simplify right side
    429.07x = 144,112.08
  5. Step 5: Solve for x
    x = 144,112.08/429.07
  6. Step 6: Final answer
    x = 335.87

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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.