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Finding the Fourth Proportional to 804.40, 1,108.79 and 656.78

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Solution

The fourth proportional to 804.40, 1,108.79 and 656.78 is: 905.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    804.40 : 1,108.79 = 656.78 : x
  2. Step 2: Convert to fraction form
    804.40/1,108.79 = 656.78/x
  3. Step 3: Cross multiply
    804.40x = 1,108.79 × 656.78
  4. Step 4: Simplify right side
    804.40x = 728,231.10
  5. Step 5: Solve for x
    x = 728,231.10/804.40
  6. Step 6: Final answer
    x = 905.31

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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.