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Finding the Fourth Proportional to 657.87, 988.22 and 639.64

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Solution

The fourth proportional to 657.87, 988.22 and 639.64 is: 960.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.87 : 988.22 = 639.64 : x
  2. Step 2: Convert to fraction form
    657.87/988.22 = 639.64/x
  3. Step 3: Cross multiply
    657.87x = 988.22 × 639.64
  4. Step 4: Simplify right side
    657.87x = 632,105.04
  5. Step 5: Solve for x
    x = 632,105.04/657.87
  6. Step 6: Final answer
    x = 960.84

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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.