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Finding the Fourth Proportional to 70.30, 105.02 and 54.05

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Solution

The fourth proportional to 70.30, 105.02 and 54.05 is: 80.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.30 : 105.02 = 54.05 : x
  2. Step 2: Convert to fraction form
    70.30/105.02 = 54.05/x
  3. Step 3: Cross multiply
    70.30x = 105.02 × 54.05
  4. Step 4: Simplify right side
    70.30x = 5,675.54
  5. Step 5: Solve for x
    x = 5,675.54/70.30
  6. Step 6: Final answer
    x = 80.74

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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.