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Finding the Fourth Proportional to 643.97, 888.50 and 378.26

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Solution

The fourth proportional to 643.97, 888.50 and 378.26 is: 521.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.97 : 888.50 = 378.26 : x
  2. Step 2: Convert to fraction form
    643.97/888.50 = 378.26/x
  3. Step 3: Cross multiply
    643.97x = 888.50 × 378.26
  4. Step 4: Simplify right side
    643.97x = 336,082.12
  5. Step 5: Solve for x
    x = 336,082.12/643.97
  6. Step 6: Final answer
    x = 521.89

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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.