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Finding the Fourth Proportional to 680.98, 939.72 and 386.29

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Solution

The fourth proportional to 680.98, 939.72 and 386.29 is: 533.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.98 : 939.72 = 386.29 : x
  2. Step 2: Convert to fraction form
    680.98/939.72 = 386.29/x
  3. Step 3: Cross multiply
    680.98x = 939.72 × 386.29
  4. Step 4: Simplify right side
    680.98x = 363,004.44
  5. Step 5: Solve for x
    x = 363,004.44/680.98
  6. Step 6: Final answer
    x = 533.06

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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.