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Finding the Fourth Proportional to 660.21, 990.65 and 440.98

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Solution

The fourth proportional to 660.21, 990.65 and 440.98 is: 661.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.21 : 990.65 = 440.98 : x
  2. Step 2: Convert to fraction form
    660.21/990.65 = 440.98/x
  3. Step 3: Cross multiply
    660.21x = 990.65 × 440.98
  4. Step 4: Simplify right side
    660.21x = 436,854.63
  5. Step 5: Solve for x
    x = 436,854.63/660.21
  6. Step 6: Final answer
    x = 661.70

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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.