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Finding the Fourth Proportional to 643.36, 887.87 and 377.80

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Solution

The fourth proportional to 643.36, 887.87 and 377.80 is: 521.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.36 : 887.87 = 377.80 : x
  2. Step 2: Convert to fraction form
    643.36/887.87 = 377.80/x
  3. Step 3: Cross multiply
    643.36x = 887.87 × 377.80
  4. Step 4: Simplify right side
    643.36x = 335,437.29
  5. Step 5: Solve for x
    x = 335,437.29/643.36
  6. Step 6: Final answer
    x = 521.38

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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.