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Finding the Fourth Proportional to 378.22, 521.97 and 220.90

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Solution

The fourth proportional to 378.22, 521.97 and 220.90 is: 304.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.22 : 521.97 = 220.90 : x
  2. Step 2: Convert to fraction form
    378.22/521.97 = 220.90/x
  3. Step 3: Cross multiply
    378.22x = 521.97 × 220.90
  4. Step 4: Simplify right side
    378.22x = 115,303.17
  5. Step 5: Solve for x
    x = 115,303.17/378.22
  6. Step 6: Final answer
    x = 304.86

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.