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Finding the Fourth Proportional to 86.16, 128.90 and 59.03

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Solution

The fourth proportional to 86.16, 128.90 and 59.03 is: 88.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    86.16 : 128.90 = 59.03 : x
  2. Step 2: Convert to fraction form
    86.16/128.90 = 59.03/x
  3. Step 3: Cross multiply
    86.16x = 128.90 × 59.03
  4. Step 4: Simplify right side
    86.16x = 7,608.47
  5. Step 5: Solve for x
    x = 7,608.47/86.16
  6. Step 6: Final answer
    x = 88.31

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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.