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Finding the Fourth Proportional to 620.48, 856.39 and 354.91

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Solution

The fourth proportional to 620.48, 856.39 and 354.91 is: 489.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.48 : 856.39 = 354.91 : x
  2. Step 2: Convert to fraction form
    620.48/856.39 = 354.91/x
  3. Step 3: Cross multiply
    620.48x = 856.39 × 354.91
  4. Step 4: Simplify right side
    620.48x = 303,941.37
  5. Step 5: Solve for x
    x = 303,941.37/620.48
  6. Step 6: Final answer
    x = 489.85

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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.