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Finding the Fourth Proportional to 378.78, 567.21 and 216.18

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Solution

The fourth proportional to 378.78, 567.21 and 216.18 is: 323.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.78 : 567.21 = 216.18 : x
  2. Step 2: Convert to fraction form
    378.78/567.21 = 216.18/x
  3. Step 3: Cross multiply
    378.78x = 567.21 × 216.18
  4. Step 4: Simplify right side
    378.78x = 122,619.46
  5. Step 5: Solve for x
    x = 122,619.46/378.78
  6. Step 6: Final answer
    x = 323.72

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.