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Finding the Fourth Proportional to 628.28, 942.40 and 217.39

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Solution

The fourth proportional to 628.28, 942.40 and 217.39 is: 326.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.28 : 942.40 = 217.39 : x
  2. Step 2: Convert to fraction form
    628.28/942.40 = 217.39/x
  3. Step 3: Cross multiply
    628.28x = 942.40 × 217.39
  4. Step 4: Simplify right side
    628.28x = 204,869.14
  5. Step 5: Solve for x
    x = 204,869.14/628.28
  6. Step 6: Final answer
    x = 326.08

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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.