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Finding the Fourth Proportional to 660.47, 990.71 and 249.60

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Solution

The fourth proportional to 660.47, 990.71 and 249.60 is: 374.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.47 : 990.71 = 249.60 : x
  2. Step 2: Convert to fraction form
    660.47/990.71 = 249.60/x
  3. Step 3: Cross multiply
    660.47x = 990.71 × 249.60
  4. Step 4: Simplify right side
    660.47x = 247,279.97
  5. Step 5: Solve for x
    x = 247,279.97/660.47
  6. Step 6: Final answer
    x = 374.40

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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.