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Finding the Fourth Proportional to 100.86, 151.28 and 86.28

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Solution

The fourth proportional to 100.86, 151.28 and 86.28 is: 129.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.86 : 151.28 = 86.28 : x
  2. Step 2: Convert to fraction form
    100.86/151.28 = 86.28/x
  3. Step 3: Cross multiply
    100.86x = 151.28 × 86.28
  4. Step 4: Simplify right side
    100.86x = 13,052.44
  5. Step 5: Solve for x
    x = 13,052.44/100.86
  6. Step 6: Final answer
    x = 129.41

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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.