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Finding the Fourth Proportional to 660.80, 912.36 and 440.20

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Solution

The fourth proportional to 660.80, 912.36 and 440.20 is: 607.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.80 : 912.36 = 440.20 : x
  2. Step 2: Convert to fraction form
    660.80/912.36 = 440.20/x
  3. Step 3: Cross multiply
    660.80x = 912.36 × 440.20
  4. Step 4: Simplify right side
    660.80x = 401,620.87
  5. Step 5: Solve for x
    x = 401,620.87/660.80
  6. Step 6: Final answer
    x = 607.78

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.