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Finding the Fourth Proportional to 660.12, 990.21 and 249.17

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Solution

The fourth proportional to 660.12, 990.21 and 249.17 is: 373.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.12 : 990.21 = 249.17 : x
  2. Step 2: Convert to fraction form
    660.12/990.21 = 249.17/x
  3. Step 3: Cross multiply
    660.12x = 990.21 × 249.17
  4. Step 4: Simplify right side
    660.12x = 246,725.67
  5. Step 5: Solve for x
    x = 246,725.67/660.12
  6. Step 6: Final answer
    x = 373.76

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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.