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Finding the Fourth Proportional to 668.14, 994.80 and 664.90

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Solution

The fourth proportional to 668.14, 994.80 and 664.90 is: 989.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.14 : 994.80 = 664.90 : x
  2. Step 2: Convert to fraction form
    668.14/994.80 = 664.90/x
  3. Step 3: Cross multiply
    668.14x = 994.80 × 664.90
  4. Step 4: Simplify right side
    668.14x = 661,442.52
  5. Step 5: Solve for x
    x = 661,442.52/668.14
  6. Step 6: Final answer
    x = 989.98

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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.