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Finding the Fourth Proportional to 70.28, 105.45 and 51.05

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Solution

The fourth proportional to 70.28, 105.45 and 51.05 is: 76.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.28 : 105.45 = 51.05 : x
  2. Step 2: Convert to fraction form
    70.28/105.45 = 51.05/x
  3. Step 3: Cross multiply
    70.28x = 105.45 × 51.05
  4. Step 4: Simplify right side
    70.28x = 5,382.99
  5. Step 5: Solve for x
    x = 5,382.99/70.28
  6. Step 6: Final answer
    x = 76.59

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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.