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Finding the Fourth Proportional to 840.06, 1,260.12 and 319.88

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Solution

The fourth proportional to 840.06, 1,260.12 and 319.88 is: 479.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    840.06 : 1,260.12 = 319.88 : x
  2. Step 2: Convert to fraction form
    840.06/1,260.12 = 319.88/x
  3. Step 3: Cross multiply
    840.06x = 1,260.12 × 319.88
  4. Step 4: Simplify right side
    840.06x = 403,091.54
  5. Step 5: Solve for x
    x = 403,091.54/840.06
  6. Step 6: Final answer
    x = 479.84

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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.