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Finding the Fourth Proportional to 79.70, 109.52 and 72.50

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Solution

The fourth proportional to 79.70, 109.52 and 72.50 is: 99.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.70 : 109.52 = 72.50 : x
  2. Step 2: Convert to fraction form
    79.70/109.52 = 72.50/x
  3. Step 3: Cross multiply
    79.70x = 109.52 × 72.50
  4. Step 4: Simplify right side
    79.70x = 7,940.20
  5. Step 5: Solve for x
    x = 7,940.20/79.70
  6. Step 6: Final answer
    x = 99.63

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.