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Finding the Fourth Proportional to 79.18, 118.21 and 72.75

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Solution

The fourth proportional to 79.18, 118.21 and 72.75 is: 108.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.18 : 118.21 = 72.75 : x
  2. Step 2: Convert to fraction form
    79.18/118.21 = 72.75/x
  3. Step 3: Cross multiply
    79.18x = 118.21 × 72.75
  4. Step 4: Simplify right side
    79.18x = 8,599.51
  5. Step 5: Solve for x
    x = 8,599.51/79.18
  6. Step 6: Final answer
    x = 108.61

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.