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Finding the Fourth Proportional to 685.05, 1,027.36 and 320.14

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Solution

The fourth proportional to 685.05, 1,027.36 and 320.14 is: 480.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.05 : 1,027.36 = 320.14 : x
  2. Step 2: Convert to fraction form
    685.05/1,027.36 = 320.14/x
  3. Step 3: Cross multiply
    685.05x = 1,027.36 × 320.14
  4. Step 4: Simplify right side
    685.05x = 328,899.03
  5. Step 5: Solve for x
    x = 328,899.03/685.05
  6. Step 6: Final answer
    x = 480.11

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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.