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Finding the Fourth Proportional to 643.26, 887.31 and 409.98

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Solution

The fourth proportional to 643.26, 887.31 and 409.98 is: 565.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.26 : 887.31 = 409.98 : x
  2. Step 2: Convert to fraction form
    643.26/887.31 = 409.98/x
  3. Step 3: Cross multiply
    643.26x = 887.31 × 409.98
  4. Step 4: Simplify right side
    643.26x = 363,779.35
  5. Step 5: Solve for x
    x = 363,779.35/643.26
  6. Step 6: Final answer
    x = 565.52

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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.