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Finding the Fourth Proportional to 79.80, 110.08 and 65.22

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Solution

The fourth proportional to 79.80, 110.08 and 65.22 is: 89.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.80 : 110.08 = 65.22 : x
  2. Step 2: Convert to fraction form
    79.80/110.08 = 65.22/x
  3. Step 3: Cross multiply
    79.80x = 110.08 × 65.22
  4. Step 4: Simplify right side
    79.80x = 7,179.42
  5. Step 5: Solve for x
    x = 7,179.42/79.80
  6. Step 6: Final answer
    x = 89.97

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.