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Finding the Fourth Proportional to 681.45, 1,022.07 and 219.15

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Solution

The fourth proportional to 681.45, 1,022.07 and 219.15 is: 328.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.45 : 1,022.07 = 219.15 : x
  2. Step 2: Convert to fraction form
    681.45/1,022.07 = 219.15/x
  3. Step 3: Cross multiply
    681.45x = 1,022.07 × 219.15
  4. Step 4: Simplify right side
    681.45x = 223,986.64
  5. Step 5: Solve for x
    x = 223,986.64/681.45
  6. Step 6: Final answer
    x = 328.69

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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.