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Finding the Fourth Proportional to 620.10, 930.15 and 209.19

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Solution

The fourth proportional to 620.10, 930.15 and 209.19 is: 313.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.10 : 930.15 = 209.19 : x
  2. Step 2: Convert to fraction form
    620.10/930.15 = 209.19/x
  3. Step 3: Cross multiply
    620.10x = 930.15 × 209.19
  4. Step 4: Simplify right side
    620.10x = 194,578.08
  5. Step 5: Solve for x
    x = 194,578.08/620.10
  6. Step 6: Final answer
    x = 313.79

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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.