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Finding the Fourth Proportional to 800.76, 1,201.23 and 390.09

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Solution

The fourth proportional to 800.76, 1,201.23 and 390.09 is: 585.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    800.76 : 1,201.23 = 390.09 : x
  2. Step 2: Convert to fraction form
    800.76/1,201.23 = 390.09/x
  3. Step 3: Cross multiply
    800.76x = 1,201.23 × 390.09
  4. Step 4: Simplify right side
    800.76x = 468,587.81
  5. Step 5: Solve for x
    x = 468,587.81/800.76
  6. Step 6: Final answer
    x = 585.18

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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.