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Finding the Fourth Proportional to 643.19, 887.60 and 377.69

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Solution

The fourth proportional to 643.19, 887.60 and 377.69 is: 521.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.19 : 887.60 = 377.69 : x
  2. Step 2: Convert to fraction form
    643.19/887.60 = 377.69/x
  3. Step 3: Cross multiply
    643.19x = 887.60 × 377.69
  4. Step 4: Simplify right side
    643.19x = 335,234.15
  5. Step 5: Solve for x
    x = 335,234.15/643.19
  6. Step 6: Final answer
    x = 521.21

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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.