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Finding the Fourth Proportional to 378.09, 521.75 and 212.31

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Solution

The fourth proportional to 378.09, 521.75 and 212.31 is: 292.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.09 : 521.75 = 212.31 : x
  2. Step 2: Convert to fraction form
    378.09/521.75 = 212.31/x
  3. Step 3: Cross multiply
    378.09x = 521.75 × 212.31
  4. Step 4: Simplify right side
    378.09x = 110,771.68
  5. Step 5: Solve for x
    x = 110,771.68/378.09
  6. Step 6: Final answer
    x = 292.98

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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.