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Finding the Fourth Proportional to 643.98, 889.47 and 560.82

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Solution

The fourth proportional to 643.98, 889.47 and 560.82 is: 774.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.98 : 889.47 = 560.82 : x
  2. Step 2: Convert to fraction form
    643.98/889.47 = 560.82/x
  3. Step 3: Cross multiply
    643.98x = 889.47 × 560.82
  4. Step 4: Simplify right side
    643.98x = 498,832.57
  5. Step 5: Solve for x
    x = 498,832.57/643.98
  6. Step 6: Final answer
    x = 774.61

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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.