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Finding the Fourth Proportional to 660.66, 991.20 and 416.86

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Solution

The fourth proportional to 660.66, 991.20 and 416.86 is: 625.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.66 : 991.20 = 416.86 : x
  2. Step 2: Convert to fraction form
    660.66/991.20 = 416.86/x
  3. Step 3: Cross multiply
    660.66x = 991.20 × 416.86
  4. Step 4: Simplify right side
    660.66x = 413,191.63
  5. Step 5: Solve for x
    x = 413,191.63/660.66
  6. Step 6: Final answer
    x = 625.42

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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.