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Finding the Fourth Proportional to 660.99, 991.14 and 331.59

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Solution

The fourth proportional to 660.99, 991.14 and 331.59 is: 497.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.99 : 991.14 = 331.59 : x
  2. Step 2: Convert to fraction form
    660.99/991.14 = 331.59/x
  3. Step 3: Cross multiply
    660.99x = 991.14 × 331.59
  4. Step 4: Simplify right side
    660.99x = 328,652.11
  5. Step 5: Solve for x
    x = 328,652.11/660.99
  6. Step 6: Final answer
    x = 497.21

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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.