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Finding the Fourth Proportional to 150.87, 208.21 and 85.39

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Solution

The fourth proportional to 150.87, 208.21 and 85.39 is: 117.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    150.87 : 208.21 = 85.39 : x
  2. Step 2: Convert to fraction form
    150.87/208.21 = 85.39/x
  3. Step 3: Cross multiply
    150.87x = 208.21 × 85.39
  4. Step 4: Simplify right side
    150.87x = 17,778.32
  5. Step 5: Solve for x
    x = 17,778.32/150.87
  6. Step 6: Final answer
    x = 117.84

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.