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Finding the Fourth Proportional to 806.56, 1,211.10 and 685.60

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Solution

The fourth proportional to 806.56, 1,211.10 and 685.60 is: 1,029.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    806.56 : 1,211.10 = 685.60 : x
  2. Step 2: Convert to fraction form
    806.56/1,211.10 = 685.60/x
  3. Step 3: Cross multiply
    806.56x = 1,211.10 × 685.60
  4. Step 4: Simplify right side
    806.56x = 830,330.16
  5. Step 5: Solve for x
    x = 830,330.16/806.56
  6. Step 6: Final answer
    x = 1,029.47

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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.