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Finding the Fourth Proportional to 685.52, 1,028.32 and 300.72

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Solution

The fourth proportional to 685.52, 1,028.32 and 300.72 is: 451.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.52 : 1,028.32 = 300.72 : x
  2. Step 2: Convert to fraction form
    685.52/1,028.32 = 300.72/x
  3. Step 3: Cross multiply
    685.52x = 1,028.32 × 300.72
  4. Step 4: Simplify right side
    685.52x = 309,236.39
  5. Step 5: Solve for x
    x = 309,236.39/685.52
  6. Step 6: Final answer
    x = 451.10

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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.