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Finding the Fourth Proportional to 628.39, 942.81 and 217.57

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Solution

The fourth proportional to 628.39, 942.81 and 217.57 is: 326.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.39 : 942.81 = 217.57 : x
  2. Step 2: Convert to fraction form
    628.39/942.81 = 217.57/x
  3. Step 3: Cross multiply
    628.39x = 942.81 × 217.57
  4. Step 4: Simplify right side
    628.39x = 205,124.81
  5. Step 5: Solve for x
    x = 205,124.81/628.39
  6. Step 6: Final answer
    x = 326.43

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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.