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Finding the Fourth Proportional to 804.80, 1,207.29 and 256.85

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Solution

The fourth proportional to 804.80, 1,207.29 and 256.85 is: 385.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    804.80 : 1,207.29 = 256.85 : x
  2. Step 2: Convert to fraction form
    804.80/1,207.29 = 256.85/x
  3. Step 3: Cross multiply
    804.80x = 1,207.29 × 256.85
  4. Step 4: Simplify right side
    804.80x = 310,092.44
  5. Step 5: Solve for x
    x = 310,092.44/804.80
  6. Step 6: Final answer
    x = 385.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.