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Finding the Fourth Proportional to 86.72, 130.10 and 79.16

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Solution

The fourth proportional to 86.72, 130.10 and 79.16 is: 118.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.72 : 130.10 = 79.16 : x
  2. Step 2: Convert to fraction form
    86.72/130.10 = 79.16/x
  3. Step 3: Cross multiply
    86.72x = 130.10 × 79.16
  4. Step 4: Simplify right side
    86.72x = 10,297.67
  5. Step 5: Solve for x
    x = 10,297.67/86.72
  6. Step 6: Final answer
    x = 118.75

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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.