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Finding the Fourth Proportional to 660.09, 989.10 and 443.40

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Solution

The fourth proportional to 660.09, 989.10 and 443.40 is: 664.40

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.09 : 989.10 = 443.40 : x
  2. Step 2: Convert to fraction form
    660.09/989.10 = 443.40/x
  3. Step 3: Cross multiply
    660.09x = 989.10 × 443.40
  4. Step 4: Simplify right side
    660.09x = 438,566.94
  5. Step 5: Solve for x
    x = 438,566.94/660.09
  6. Step 6: Final answer
    x = 664.40

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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.