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Finding the Fourth Proportional to 620.77, 856.49 and 443.78

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Solution

The fourth proportional to 620.77, 856.49 and 443.78 is: 612.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.77 : 856.49 = 443.78 : x
  2. Step 2: Convert to fraction form
    620.77/856.49 = 443.78/x
  3. Step 3: Cross multiply
    620.77x = 856.49 × 443.78
  4. Step 4: Simplify right side
    620.77x = 380,093.13
  5. Step 5: Solve for x
    x = 380,093.13/620.77
  6. Step 6: Final answer
    x = 612.29

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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.