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Finding the Fourth Proportional to 70.60, 105.20 and 66.05

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Solution

The fourth proportional to 70.60, 105.20 and 66.05 is: 98.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    70.60 : 105.20 = 66.05 : x
  2. Step 2: Convert to fraction form
    70.60/105.20 = 66.05/x
  3. Step 3: Cross multiply
    70.60x = 105.20 × 66.05
  4. Step 4: Simplify right side
    70.60x = 6,947.93
  5. Step 5: Solve for x
    x = 6,947.93/70.60
  6. Step 6: Final answer
    x = 98.41

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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.