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Finding the Fourth Proportional to 813.05, 1,121.21 and 745.60

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Solution

The fourth proportional to 813.05, 1,121.21 and 745.60 is: 1,028.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    813.05 : 1,121.21 = 745.60 : x
  2. Step 2: Convert to fraction form
    813.05/1,121.21 = 745.60/x
  3. Step 3: Cross multiply
    813.05x = 1,121.21 × 745.60
  4. Step 4: Simplify right side
    813.05x = 835,974.18
  5. Step 5: Solve for x
    x = 835,974.18/813.05
  6. Step 6: Final answer
    x = 1,028.20

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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.