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Finding the Fourth Proportional to 431.93, 650.80 and 390.85

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Solution

The fourth proportional to 431.93, 650.80 and 390.85 is: 588.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    431.93 : 650.80 = 390.85 : x
  2. Step 2: Convert to fraction form
    431.93/650.80 = 390.85/x
  3. Step 3: Cross multiply
    431.93x = 650.80 × 390.85
  4. Step 4: Simplify right side
    431.93x = 254,361.93
  5. Step 5: Solve for x
    x = 254,361.93/431.93
  6. Step 6: Final answer
    x = 588.90

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.