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Finding the Fourth Proportional to 155.09, 214.01 and 85.15

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Solution

The fourth proportional to 155.09, 214.01 and 85.15 is: 117.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.09 : 214.01 = 85.15 : x
  2. Step 2: Convert to fraction form
    155.09/214.01 = 85.15/x
  3. Step 3: Cross multiply
    155.09x = 214.01 × 85.15
  4. Step 4: Simplify right side
    155.09x = 18,222.47
  5. Step 5: Solve for x
    x = 18,222.47/155.09
  6. Step 6: Final answer
    x = 117.50

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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.