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Finding the Fourth Proportional to 378.75, 522.68 and 221.37

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Solution

The fourth proportional to 378.75, 522.68 and 221.37 is: 305.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.75 : 522.68 = 221.37 : x
  2. Step 2: Convert to fraction form
    378.75/522.68 = 221.37/x
  3. Step 3: Cross multiply
    378.75x = 522.68 × 221.37
  4. Step 4: Simplify right side
    378.75x = 115,705.67
  5. Step 5: Solve for x
    x = 115,705.67/378.75
  6. Step 6: Final answer
    x = 305.49

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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.