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Finding the Fourth Proportional to 388.19, 538.02 and 380.90

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Solution

The fourth proportional to 388.19, 538.02 and 380.90 is: 527.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.19 : 538.02 = 380.90 : x
  2. Step 2: Convert to fraction form
    388.19/538.02 = 380.90/x
  3. Step 3: Cross multiply
    388.19x = 538.02 × 380.90
  4. Step 4: Simplify right side
    388.19x = 204,932.74
  5. Step 5: Solve for x
    x = 204,932.74/388.19
  6. Step 6: Final answer
    x = 527.91

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.