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Finding the Fourth Proportional to 620.82, 856.89 and 388.26

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Solution

The fourth proportional to 620.82, 856.89 and 388.26 is: 535.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.82 : 856.89 = 388.26 : x
  2. Step 2: Convert to fraction form
    620.82/856.89 = 388.26/x
  3. Step 3: Cross multiply
    620.82x = 856.89 × 388.26
  4. Step 4: Simplify right side
    620.82x = 332,696.11
  5. Step 5: Solve for x
    x = 332,696.11/620.82
  6. Step 6: Final answer
    x = 535.90

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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.