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Finding the Fourth Proportional to 643.38, 887.80 and 359.75

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Solution

The fourth proportional to 643.38, 887.80 and 359.75 is: 496.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.38 : 887.80 = 359.75 : x
  2. Step 2: Convert to fraction form
    643.38/887.80 = 359.75/x
  3. Step 3: Cross multiply
    643.38x = 887.80 × 359.75
  4. Step 4: Simplify right side
    643.38x = 319,379.81
  5. Step 5: Solve for x
    x = 319,379.81/643.38
  6. Step 6: Final answer
    x = 496.41

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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.