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Finding the Fourth Proportional to 1,218.92, 1,682.12 and 680.56

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Solution

The fourth proportional to 1,218.92, 1,682.12 and 680.56 is: 939.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,218.92 : 1,682.12 = 680.56 : x
  2. Step 2: Convert to fraction form
    1,218.92/1,682.12 = 680.56/x
  3. Step 3: Cross multiply
    1,218.92x = 1,682.12 × 680.56
  4. Step 4: Simplify right side
    1,218.92x = 1,144,781.99
  5. Step 5: Solve for x
    x = 1,144,781.99/1,218.92
  6. Step 6: Final answer
    x = 939.17

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.