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Finding the Fourth Proportional to 783.20, 1,080.81 and 451.61

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Solution

The fourth proportional to 783.20, 1,080.81 and 451.61 is: 623.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    783.20 : 1,080.81 = 451.61 : x
  2. Step 2: Convert to fraction form
    783.20/1,080.81 = 451.61/x
  3. Step 3: Cross multiply
    783.20x = 1,080.81 × 451.61
  4. Step 4: Simplify right side
    783.20x = 488,099.20
  5. Step 5: Solve for x
    x = 488,099.20/783.20
  6. Step 6: Final answer
    x = 623.22

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.