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Finding the Fourth Proportional to 643.01, 887.25 and 406.85

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Solution

The fourth proportional to 643.01, 887.25 and 406.85 is: 561.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.01 : 887.25 = 406.85 : x
  2. Step 2: Convert to fraction form
    643.01/887.25 = 406.85/x
  3. Step 3: Cross multiply
    643.01x = 887.25 × 406.85
  4. Step 4: Simplify right side
    643.01x = 360,973.23
  5. Step 5: Solve for x
    x = 360,973.23/643.01
  6. Step 6: Final answer
    x = 561.38

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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.