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Finding the Fourth Proportional to 78.90, 118.11 and 48.36

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Solution

The fourth proportional to 78.90, 118.11 and 48.36 is: 72.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.90 : 118.11 = 48.36 : x
  2. Step 2: Convert to fraction form
    78.90/118.11 = 48.36/x
  3. Step 3: Cross multiply
    78.90x = 118.11 × 48.36
  4. Step 4: Simplify right side
    78.90x = 5,711.80
  5. Step 5: Solve for x
    x = 5,711.80/78.90
  6. Step 6: Final answer
    x = 72.39

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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.