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Finding the Fourth Proportional to 620.55, 930.89 and 209.72

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Solution

The fourth proportional to 620.55, 930.89 and 209.72 is: 314.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.55 : 930.89 = 209.72 : x
  2. Step 2: Convert to fraction form
    620.55/930.89 = 209.72/x
  3. Step 3: Cross multiply
    620.55x = 930.89 × 209.72
  4. Step 4: Simplify right side
    620.55x = 195,220.55
  5. Step 5: Solve for x
    x = 195,220.55/620.55
  6. Step 6: Final answer
    x = 314.59

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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.