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Finding the Fourth Proportional to 378.13, 521.81 and 220.77

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Solution

The fourth proportional to 378.13, 521.81 and 220.77 is: 304.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.13 : 521.81 = 220.77 : x
  2. Step 2: Convert to fraction form
    378.13/521.81 = 220.77/x
  3. Step 3: Cross multiply
    378.13x = 521.81 × 220.77
  4. Step 4: Simplify right side
    378.13x = 115,199.87
  5. Step 5: Solve for x
    x = 115,199.87/378.13
  6. Step 6: Final answer
    x = 304.66

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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.