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Finding the Fourth Proportional to 685, 1,027.50 and 300.25

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Solution

The fourth proportional to 685, 1,027.50 and 300.25 is: 450.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    685 : 1,027.50 = 300.25 : x
  2. Step 2: Convert to fraction form
    685/1,027.50 = 300.25/x
  3. Step 3: Cross multiply
    685x = 1,027.50 × 300.25
  4. Step 4: Simplify right side
    685x = 308,506.88
  5. Step 5: Solve for x
    x = 308,506.88/685
  6. Step 6: Final answer
    x = 450.38

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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.