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Finding the Fourth Proportional to 806.30, 1,213.56 and 687.36

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Solution

The fourth proportional to 806.30, 1,213.56 and 687.36 is: 1,034.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.30 : 1,213.56 = 687.36 : x
  2. Step 2: Convert to fraction form
    806.30/1,213.56 = 687.36/x
  3. Step 3: Cross multiply
    806.30x = 1,213.56 × 687.36
  4. Step 4: Simplify right side
    806.30x = 834,152.60
  5. Step 5: Solve for x
    x = 834,152.60/806.30
  6. Step 6: Final answer
    x = 1,034.54

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.