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Finding the Fourth Proportional to 378.69, 521.80 and 304.71

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Solution

The fourth proportional to 378.69, 521.80 and 304.71 is: 419.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.69 : 521.80 = 304.71 : x
  2. Step 2: Convert to fraction form
    378.69/521.80 = 304.71/x
  3. Step 3: Cross multiply
    378.69x = 521.80 × 304.71
  4. Step 4: Simplify right side
    378.69x = 158,997.68
  5. Step 5: Solve for x
    x = 158,997.68/378.69
  6. Step 6: Final answer
    x = 419.86

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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.