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Finding the Fourth Proportional to 649.05, 969.04 and 642.21

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Solution

The fourth proportional to 649.05, 969.04 and 642.21 is: 958.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.05 : 969.04 = 642.21 : x
  2. Step 2: Convert to fraction form
    649.05/969.04 = 642.21/x
  3. Step 3: Cross multiply
    649.05x = 969.04 × 642.21
  4. Step 4: Simplify right side
    649.05x = 622,325.57
  5. Step 5: Solve for x
    x = 622,325.57/649.05
  6. Step 6: Final answer
    x = 958.83

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.