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Finding the Fourth Proportional to 685.83, 1,028.61 and 439.05

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Solution

The fourth proportional to 685.83, 1,028.61 and 439.05 is: 658.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    685.83 : 1,028.61 = 439.05 : x
  2. Step 2: Convert to fraction form
    685.83/1,028.61 = 439.05/x
  3. Step 3: Cross multiply
    685.83x = 1,028.61 × 439.05
  4. Step 4: Simplify right side
    685.83x = 451,611.22
  5. Step 5: Solve for x
    x = 451,611.22/685.83
  6. Step 6: Final answer
    x = 658.49

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1.5x scale

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.