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Finding the Fourth Proportional to 660.77, 991.04 and 485.81

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Solution

The fourth proportional to 660.77, 991.04 and 485.81 is: 728.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.77 : 991.04 = 485.81 : x
  2. Step 2: Convert to fraction form
    660.77/991.04 = 485.81/x
  3. Step 3: Cross multiply
    660.77x = 991.04 × 485.81
  4. Step 4: Simplify right side
    660.77x = 481,459.05
  5. Step 5: Solve for x
    x = 481,459.05/660.77
  6. Step 6: Final answer
    x = 728.63

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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.