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Finding the Fourth Proportional to 621.21, 931.94 and 210.39

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Solution

The fourth proportional to 621.21, 931.94 and 210.39 is: 315.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.21 : 931.94 = 210.39 : x
  2. Step 2: Convert to fraction form
    621.21/931.94 = 210.39/x
  3. Step 3: Cross multiply
    621.21x = 931.94 × 210.39
  4. Step 4: Simplify right side
    621.21x = 196,069.80
  5. Step 5: Solve for x
    x = 196,069.80/621.21
  6. Step 6: Final answer
    x = 315.63

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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.