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Finding the Fourth Proportional to 628.47, 942.78 and 217.70

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Solution

The fourth proportional to 628.47, 942.78 and 217.70 is: 326.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.47 : 942.78 = 217.70 : x
  2. Step 2: Convert to fraction form
    628.47/942.78 = 217.70/x
  3. Step 3: Cross multiply
    628.47x = 942.78 × 217.70
  4. Step 4: Simplify right side
    628.47x = 205,243.21
  5. Step 5: Solve for x
    x = 205,243.21/628.47
  6. Step 6: Final answer
    x = 326.58

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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.