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Finding the Fourth Proportional to 660.36, 990.25 and 249.21

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Solution

The fourth proportional to 660.36, 990.25 and 249.21 is: 373.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.36 : 990.25 = 249.21 : x
  2. Step 2: Convert to fraction form
    660.36/990.25 = 249.21/x
  3. Step 3: Cross multiply
    660.36x = 990.25 × 249.21
  4. Step 4: Simplify right side
    660.36x = 246,780.20
  5. Step 5: Solve for x
    x = 246,780.20/660.36
  6. Step 6: Final answer
    x = 373.71

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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.