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Finding the Fourth Proportional to 100.28, 150.28 and 69.90

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Solution

The fourth proportional to 100.28, 150.28 and 69.90 is: 104.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.28 : 150.28 = 69.90 : x
  2. Step 2: Convert to fraction form
    100.28/150.28 = 69.90/x
  3. Step 3: Cross multiply
    100.28x = 150.28 × 69.90
  4. Step 4: Simplify right side
    100.28x = 10,504.57
  5. Step 5: Solve for x
    x = 10,504.57/100.28
  6. Step 6: Final answer
    x = 104.75

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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.