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Finding the Fourth Proportional to 660.91, 991.52 and 309.47

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Solution

The fourth proportional to 660.91, 991.52 and 309.47 is: 464.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.91 : 991.52 = 309.47 : x
  2. Step 2: Convert to fraction form
    660.91/991.52 = 309.47/x
  3. Step 3: Cross multiply
    660.91x = 991.52 × 309.47
  4. Step 4: Simplify right side
    660.91x = 306,847.67
  5. Step 5: Solve for x
    x = 306,847.67/660.91
  6. Step 6: Final answer
    x = 464.28

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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.