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Finding the Fourth Proportional to 660.65, 990.38 and 249.71

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Solution

The fourth proportional to 660.65, 990.38 and 249.71 is: 374.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.65 : 990.38 = 249.71 : x
  2. Step 2: Convert to fraction form
    660.65/990.38 = 249.71/x
  3. Step 3: Cross multiply
    660.65x = 990.38 × 249.71
  4. Step 4: Simplify right side
    660.65x = 247,301.59
  5. Step 5: Solve for x
    x = 247,301.59/660.65
  6. Step 6: Final answer
    x = 374.33

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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.