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Finding the Fourth Proportional to 135.84, 203.94 and 78.12

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Solution

The fourth proportional to 135.84, 203.94 and 78.12 is: 117.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    135.84 : 203.94 = 78.12 : x
  2. Step 2: Convert to fraction form
    135.84/203.94 = 78.12/x
  3. Step 3: Cross multiply
    135.84x = 203.94 × 78.12
  4. Step 4: Simplify right side
    135.84x = 15,931.79
  5. Step 5: Solve for x
    x = 15,931.79/135.84
  6. Step 6: Final answer
    x = 117.28

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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.