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Finding the Fourth Proportional to 668.36, 998.10 and 661.12

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Solution

The fourth proportional to 668.36, 998.10 and 661.12 is: 987.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.36 : 998.10 = 661.12 : x
  2. Step 2: Convert to fraction form
    668.36/998.10 = 661.12/x
  3. Step 3: Cross multiply
    668.36x = 998.10 × 661.12
  4. Step 4: Simplify right side
    668.36x = 659,863.87
  5. Step 5: Solve for x
    x = 659,863.87/668.36
  6. Step 6: Final answer
    x = 987.29

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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.