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Finding the Fourth Proportional to 252.09, 378.20 and 89.78

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Solution

The fourth proportional to 252.09, 378.20 and 89.78 is: 134.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    252.09 : 378.20 = 89.78 : x
  2. Step 2: Convert to fraction form
    252.09/378.20 = 89.78/x
  3. Step 3: Cross multiply
    252.09x = 378.20 × 89.78
  4. Step 4: Simplify right side
    252.09x = 33,955.97
  5. Step 5: Solve for x
    x = 33,955.97/252.09
  6. Step 6: Final answer
    x = 134.70

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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.