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Finding the Fourth Proportional to 70.02, 105.09 and 50.78

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Solution

The fourth proportional to 70.02, 105.09 and 50.78 is: 76.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.02 : 105.09 = 50.78 : x
  2. Step 2: Convert to fraction form
    70.02/105.09 = 50.78/x
  3. Step 3: Cross multiply
    70.02x = 105.09 × 50.78
  4. Step 4: Simplify right side
    70.02x = 5,336.47
  5. Step 5: Solve for x
    x = 5,336.47/70.02
  6. Step 6: Final answer
    x = 76.21

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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.