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Finding the Fourth Proportional to 660.87, 991.17 and 228.15

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Solution

The fourth proportional to 660.87, 991.17 and 228.15 is: 342.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.87 : 991.17 = 228.15 : x
  2. Step 2: Convert to fraction form
    660.87/991.17 = 228.15/x
  3. Step 3: Cross multiply
    660.87x = 991.17 × 228.15
  4. Step 4: Simplify right side
    660.87x = 226,135.44
  5. Step 5: Solve for x
    x = 226,135.44/660.87
  6. Step 6: Final answer
    x = 342.18

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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.