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Finding the Fourth Proportional to 137.30, 189.49 and 78.29

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Solution

The fourth proportional to 137.30, 189.49 and 78.29 is: 108.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    137.30 : 189.49 = 78.29 : x
  2. Step 2: Convert to fraction form
    137.30/189.49 = 78.29/x
  3. Step 3: Cross multiply
    137.30x = 189.49 × 78.29
  4. Step 4: Simplify right side
    137.30x = 14,835.17
  5. Step 5: Solve for x
    x = 14,835.17/137.30
  6. Step 6: Final answer
    x = 108.05

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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.