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Finding the Fourth Proportional to 680.51, 939.09 and 400.76

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Solution

The fourth proportional to 680.51, 939.09 and 400.76 is: 553.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.51 : 939.09 = 400.76 : x
  2. Step 2: Convert to fraction form
    680.51/939.09 = 400.76/x
  3. Step 3: Cross multiply
    680.51x = 939.09 × 400.76
  4. Step 4: Simplify right side
    680.51x = 376,351.36
  5. Step 5: Solve for x
    x = 376,351.36/680.51
  6. Step 6: Final answer
    x = 553.04

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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.