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Finding the Fourth Proportional to 643.88, 888.59 and 378.33

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Solution

The fourth proportional to 643.88, 888.59 and 378.33 is: 522.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.88 : 888.59 = 378.33 : x
  2. Step 2: Convert to fraction form
    643.88/888.59 = 378.33/x
  3. Step 3: Cross multiply
    643.88x = 888.59 × 378.33
  4. Step 4: Simplify right side
    643.88x = 336,176.14
  5. Step 5: Solve for x
    x = 336,176.14/643.88
  6. Step 6: Final answer
    x = 522.11

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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.