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Finding the Fourth Proportional to 79.80, 110.05 and 64.25

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Solution

The fourth proportional to 79.80, 110.05 and 64.25 is: 88.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.80 : 110.05 = 64.25 : x
  2. Step 2: Convert to fraction form
    79.80/110.05 = 64.25/x
  3. Step 3: Cross multiply
    79.80x = 110.05 × 64.25
  4. Step 4: Simplify right side
    79.80x = 7,070.81
  5. Step 5: Solve for x
    x = 7,070.81/79.80
  6. Step 6: Final answer
    x = 88.61

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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.