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Finding the Fourth Proportional to 91.98, 137.12 and 79.20

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Solution

The fourth proportional to 91.98, 137.12 and 79.20 is: 118.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    91.98 : 137.12 = 79.20 : x
  2. Step 2: Convert to fraction form
    91.98/137.12 = 79.20/x
  3. Step 3: Cross multiply
    91.98x = 137.12 × 79.20
  4. Step 4: Simplify right side
    91.98x = 10,859.51
  5. Step 5: Solve for x
    x = 10,859.51/91.98
  6. Step 6: Final answer
    x = 118.06

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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.