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Finding the Fourth Proportional to 681.61, 1,021.74 and 219.05

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Solution

The fourth proportional to 681.61, 1,021.74 and 219.05 is: 328.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.61 : 1,021.74 = 219.05 : x
  2. Step 2: Convert to fraction form
    681.61/1,021.74 = 219.05/x
  3. Step 3: Cross multiply
    681.61x = 1,021.74 × 219.05
  4. Step 4: Simplify right side
    681.61x = 223,809.59
  5. Step 5: Solve for x
    x = 223,809.59/681.61
  6. Step 6: Final answer
    x = 328.36

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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.