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Finding the Fourth Proportional to 378.47, 521.79 and 247.25

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Solution

The fourth proportional to 378.47, 521.79 and 247.25 is: 340.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.47 : 521.79 = 247.25 : x
  2. Step 2: Convert to fraction form
    378.47/521.79 = 247.25/x
  3. Step 3: Cross multiply
    378.47x = 521.79 × 247.25
  4. Step 4: Simplify right side
    378.47x = 129,012.58
  5. Step 5: Solve for x
    x = 129,012.58/378.47
  6. Step 6: Final answer
    x = 340.88

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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.