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Finding the Fourth Proportional to 642.60, 961.83 and 447.84

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Solution

The fourth proportional to 642.60, 961.83 and 447.84 is: 670.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    642.60 : 961.83 = 447.84 : x
  2. Step 2: Convert to fraction form
    642.60/961.83 = 447.84/x
  3. Step 3: Cross multiply
    642.60x = 961.83 × 447.84
  4. Step 4: Simplify right side
    642.60x = 430,745.95
  5. Step 5: Solve for x
    x = 430,745.95/642.60
  6. Step 6: Final answer
    x = 670.32

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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.