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Finding the Fourth Proportional to 840.14, 1,261.13 and 620.09

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Solution

The fourth proportional to 840.14, 1,261.13 and 620.09 is: 930.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.14 : 1,261.13 = 620.09 : x
  2. Step 2: Convert to fraction form
    840.14/1,261.13 = 620.09/x
  3. Step 3: Cross multiply
    840.14x = 1,261.13 × 620.09
  4. Step 4: Simplify right side
    840.14x = 782,014.10
  5. Step 5: Solve for x
    x = 782,014.10/840.14
  6. Step 6: Final answer
    x = 930.81

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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.