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Finding the Fourth Proportional to 620.39, 930.68 and 203.79

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Solution

The fourth proportional to 620.39, 930.68 and 203.79 is: 305.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.39 : 930.68 = 203.79 : x
  2. Step 2: Convert to fraction form
    620.39/930.68 = 203.79/x
  3. Step 3: Cross multiply
    620.39x = 930.68 × 203.79
  4. Step 4: Simplify right side
    620.39x = 189,663.28
  5. Step 5: Solve for x
    x = 189,663.28/620.39
  6. Step 6: Final answer
    x = 305.72

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.