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Finding the Fourth Proportional to 79.42, 108.91 and 72.10

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Solution

The fourth proportional to 79.42, 108.91 and 72.10 is: 98.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.42 : 108.91 = 72.10 : x
  2. Step 2: Convert to fraction form
    79.42/108.91 = 72.10/x
  3. Step 3: Cross multiply
    79.42x = 108.91 × 72.10
  4. Step 4: Simplify right side
    79.42x = 7,852.41
  5. Step 5: Solve for x
    x = 7,852.41/79.42
  6. Step 6: Final answer
    x = 98.87

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.