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Finding the Fourth Proportional to 806.36, 1,204.40 and 643.56

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Solution

The fourth proportional to 806.36, 1,204.40 and 643.56 is: 961.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.36 : 1,204.40 = 643.56 : x
  2. Step 2: Convert to fraction form
    806.36/1,204.40 = 643.56/x
  3. Step 3: Cross multiply
    806.36x = 1,204.40 × 643.56
  4. Step 4: Simplify right side
    806.36x = 775,103.66
  5. Step 5: Solve for x
    x = 775,103.66/806.36
  6. Step 6: Final answer
    x = 961.24

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.