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Finding the Fourth Proportional to 869.31, 1,304.15 and 407.61

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Solution

The fourth proportional to 869.31, 1,304.15 and 407.61 is: 611.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.31 : 1,304.15 = 407.61 : x
  2. Step 2: Convert to fraction form
    869.31/1,304.15 = 407.61/x
  3. Step 3: Cross multiply
    869.31x = 1,304.15 × 407.61
  4. Step 4: Simplify right side
    869.31x = 531,582.54
  5. Step 5: Solve for x
    x = 531,582.54/869.31
  6. Step 6: Final answer
    x = 611.50

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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.