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Finding the Fourth Proportional to 643.47, 887.81 and 377.76

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Solution

The fourth proportional to 643.47, 887.81 and 377.76 is: 521.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.47 : 887.81 = 377.76 : x
  2. Step 2: Convert to fraction form
    643.47/887.81 = 377.76/x
  3. Step 3: Cross multiply
    643.47x = 887.81 × 377.76
  4. Step 4: Simplify right side
    643.47x = 335,377.22
  5. Step 5: Solve for x
    x = 335,377.22/643.47
  6. Step 6: Final answer
    x = 521.20

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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.