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Finding the Fourth Proportional to 640.93, 878.71 and 629.25

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Solution

The fourth proportional to 640.93, 878.71 and 629.25 is: 862.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.93 : 878.71 = 629.25 : x
  2. Step 2: Convert to fraction form
    640.93/878.71 = 629.25/x
  3. Step 3: Cross multiply
    640.93x = 878.71 × 629.25
  4. Step 4: Simplify right side
    640.93x = 552,924.50
  5. Step 5: Solve for x
    x = 552,924.50/640.93
  6. Step 6: Final answer
    x = 862.70

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.