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Finding the Fourth Proportional to 378.58, 522.36 and 221.18

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Solution

The fourth proportional to 378.58, 522.36 and 221.18 is: 305.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.58 : 522.36 = 221.18 : x
  2. Step 2: Convert to fraction form
    378.58/522.36 = 221.18/x
  3. Step 3: Cross multiply
    378.58x = 522.36 × 221.18
  4. Step 4: Simplify right side
    378.58x = 115,535.58
  5. Step 5: Solve for x
    x = 115,535.58/378.58
  6. Step 6: Final answer
    x = 305.18

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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.