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Finding the Fourth Proportional to 660.65, 991.69 and 486.78

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Solution

The fourth proportional to 660.65, 991.69 and 486.78 is: 730.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.65 : 991.69 = 486.78 : x
  2. Step 2: Convert to fraction form
    660.65/991.69 = 486.78/x
  3. Step 3: Cross multiply
    660.65x = 991.69 × 486.78
  4. Step 4: Simplify right side
    660.65x = 482,729.92
  5. Step 5: Solve for x
    x = 482,729.92/660.65
  6. Step 6: Final answer
    x = 730.69

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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.