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Finding the Fourth Proportional to 869.82, 1,304.91 and 747.78

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Solution

The fourth proportional to 869.82, 1,304.91 and 747.78 is: 1,121.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.82 : 1,304.91 = 747.78 : x
  2. Step 2: Convert to fraction form
    869.82/1,304.91 = 747.78/x
  3. Step 3: Cross multiply
    869.82x = 1,304.91 × 747.78
  4. Step 4: Simplify right side
    869.82x = 975,785.60
  5. Step 5: Solve for x
    x = 975,785.60/869.82
  6. Step 6: Final answer
    x = 1,121.82

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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.