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Finding the Fourth Proportional to 72.70, 108.98 and 66.70

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Solution

The fourth proportional to 72.70, 108.98 and 66.70 is: 99.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    72.70 : 108.98 = 66.70 : x
  2. Step 2: Convert to fraction form
    72.70/108.98 = 66.70/x
  3. Step 3: Cross multiply
    72.70x = 108.98 × 66.70
  4. Step 4: Simplify right side
    72.70x = 7,268.97
  5. Step 5: Solve for x
    x = 7,268.97/72.70
  6. Step 6: Final answer
    x = 99.99

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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.