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Finding the Fourth Proportional to 378.63, 522.50 and 221.22

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Solution

The fourth proportional to 378.63, 522.50 and 221.22 is: 305.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.63 : 522.50 = 221.22 : x
  2. Step 2: Convert to fraction form
    378.63/522.50 = 221.22/x
  3. Step 3: Cross multiply
    378.63x = 522.50 × 221.22
  4. Step 4: Simplify right side
    378.63x = 115,586.34
  5. Step 5: Solve for x
    x = 115,586.34/378.63
  6. Step 6: Final answer
    x = 305.28

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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.