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Finding the Fourth Proportional to 680.91, 939.77 and 386.34

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Solution

The fourth proportional to 680.91, 939.77 and 386.34 is: 533.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    680.91 : 939.77 = 386.34 : x
  2. Step 2: Convert to fraction form
    680.91/939.77 = 386.34/x
  3. Step 3: Cross multiply
    680.91x = 939.77 × 386.34
  4. Step 4: Simplify right side
    680.91x = 363,074.66
  5. Step 5: Solve for x
    x = 363,074.66/680.91
  6. Step 6: Final answer
    x = 533.22

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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.