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Finding the Fourth Proportional to 660.45, 988.34 and 486.71

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Solution

The fourth proportional to 660.45, 988.34 and 486.71 is: 728.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.45 : 988.34 = 486.71 : x
  2. Step 2: Convert to fraction form
    660.45/988.34 = 486.71/x
  3. Step 3: Cross multiply
    660.45x = 988.34 × 486.71
  4. Step 4: Simplify right side
    660.45x = 481,027.59
  5. Step 5: Solve for x
    x = 481,027.59/660.45
  6. Step 6: Final answer
    x = 728.33

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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.