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Finding the Fourth Proportional to 100.60, 150.08 and 85.21

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Solution

The fourth proportional to 100.60, 150.08 and 85.21 is: 127.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.60 : 150.08 = 85.21 : x
  2. Step 2: Convert to fraction form
    100.60/150.08 = 85.21/x
  3. Step 3: Cross multiply
    100.60x = 150.08 × 85.21
  4. Step 4: Simplify right side
    100.60x = 12,787.99
  5. Step 5: Solve for x
    x = 12,787.99/100.60
  6. Step 6: Final answer
    x = 127.12

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.