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Finding the Fourth Proportional to 630.21, 945.80 and 219.71

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Solution

The fourth proportional to 630.21, 945.80 and 219.71 is: 329.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.21 : 945.80 = 219.71 : x
  2. Step 2: Convert to fraction form
    630.21/945.80 = 219.71/x
  3. Step 3: Cross multiply
    630.21x = 945.80 × 219.71
  4. Step 4: Simplify right side
    630.21x = 207,795.89
  5. Step 5: Solve for x
    x = 207,795.89/630.21
  6. Step 6: Final answer
    x = 329.72

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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.