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Finding the Fourth Proportional to 628.57, 942.87 and 217.70

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Solution

The fourth proportional to 628.57, 942.87 and 217.70 is: 326.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.57 : 942.87 = 217.70 : x
  2. Step 2: Convert to fraction form
    628.57/942.87 = 217.70/x
  3. Step 3: Cross multiply
    628.57x = 942.87 × 217.70
  4. Step 4: Simplify right side
    628.57x = 205,261.71
  5. Step 5: Solve for x
    x = 205,261.71/628.57
  6. Step 6: Final answer
    x = 326.55

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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.