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Finding the Fourth Proportional to 620.91, 931.05 and 209.97

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Solution

The fourth proportional to 620.91, 931.05 and 209.97 is: 314.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.91 : 931.05 = 209.97 : x
  2. Step 2: Convert to fraction form
    620.91/931.05 = 209.97/x
  3. Step 3: Cross multiply
    620.91x = 931.05 × 209.97
  4. Step 4: Simplify right side
    620.91x = 195,492.57
  5. Step 5: Solve for x
    x = 195,492.57/620.91
  6. Step 6: Final answer
    x = 314.85

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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.