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Finding the Fourth Proportional to 840.39, 1,260.74 and 320.37

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Solution

The fourth proportional to 840.39, 1,260.74 and 320.37 is: 480.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.39 : 1,260.74 = 320.37 : x
  2. Step 2: Convert to fraction form
    840.39/1,260.74 = 320.37/x
  3. Step 3: Cross multiply
    840.39x = 1,260.74 × 320.37
  4. Step 4: Simplify right side
    840.39x = 403,903.27
  5. Step 5: Solve for x
    x = 403,903.27/840.39
  6. Step 6: Final answer
    x = 480.61

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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.