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Finding the Fourth Proportional to 643.71, 888.62 and 431.38

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Solution

The fourth proportional to 643.71, 888.62 and 431.38 is: 595.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.71 : 888.62 = 431.38 : x
  2. Step 2: Convert to fraction form
    643.71/888.62 = 431.38/x
  3. Step 3: Cross multiply
    643.71x = 888.62 × 431.38
  4. Step 4: Simplify right side
    643.71x = 383,330.74
  5. Step 5: Solve for x
    x = 383,330.74/643.71
  6. Step 6: Final answer
    x = 595.51

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.