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Finding the Fourth Proportional to 620.70, 931.08 and 209.91

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Solution

The fourth proportional to 620.70, 931.08 and 209.91 is: 314.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.70 : 931.08 = 209.91 : x
  2. Step 2: Convert to fraction form
    620.70/931.08 = 209.91/x
  3. Step 3: Cross multiply
    620.70x = 931.08 × 209.91
  4. Step 4: Simplify right side
    620.70x = 195,443.00
  5. Step 5: Solve for x
    x = 195,443.00/620.70
  6. Step 6: Final answer
    x = 314.88

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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.