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Finding the Fourth Proportional to 666.27, 990.41 and 646.58

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Solution

The fourth proportional to 666.27, 990.41 and 646.58 is: 961.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    666.27 : 990.41 = 646.58 : x
  2. Step 2: Convert to fraction form
    666.27/990.41 = 646.58/x
  3. Step 3: Cross multiply
    666.27x = 990.41 × 646.58
  4. Step 4: Simplify right side
    666.27x = 640,379.30
  5. Step 5: Solve for x
    x = 640,379.30/666.27
  6. Step 6: Final answer
    x = 961.15

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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.