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Finding the Fourth Proportional to 78.80, 118.12 and 36

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Solution

The fourth proportional to 78.80, 118.12 and 36 is: 53.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.80 : 118.12 = 36 : x
  2. Step 2: Convert to fraction form
    78.80/118.12 = 36/x
  3. Step 3: Cross multiply
    78.80x = 118.12 × 36
  4. Step 4: Simplify right side
    78.80x = 4,252.32
  5. Step 5: Solve for x
    x = 4,252.32/78.80
  6. Step 6: Final answer
    x = 53.96

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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.