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Finding the Fourth Proportional to 645.93, 969.98 and 640.89

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Solution

The fourth proportional to 645.93, 969.98 and 640.89 is: 962.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.93 : 969.98 = 640.89 : x
  2. Step 2: Convert to fraction form
    645.93/969.98 = 640.89/x
  3. Step 3: Cross multiply
    645.93x = 969.98 × 640.89
  4. Step 4: Simplify right side
    645.93x = 621,647.28
  5. Step 5: Solve for x
    x = 621,647.28/645.93
  6. Step 6: Final answer
    x = 962.41

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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.