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Finding the Fourth Proportional to 506.91, 699.34 and 388.90

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Solution

The fourth proportional to 506.91, 699.34 and 388.90 is: 536.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    506.91 : 699.34 = 388.90 : x
  2. Step 2: Convert to fraction form
    506.91/699.34 = 388.90/x
  3. Step 3: Cross multiply
    506.91x = 699.34 × 388.90
  4. Step 4: Simplify right side
    506.91x = 271,973.33
  5. Step 5: Solve for x
    x = 271,973.33/506.91
  6. Step 6: Final answer
    x = 536.53

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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.