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Finding the Fourth Proportional to 79.70, 109.76 and 64.14

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Solution

The fourth proportional to 79.70, 109.76 and 64.14 is: 88.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.70 : 109.76 = 64.14 : x
  2. Step 2: Convert to fraction form
    79.70/109.76 = 64.14/x
  3. Step 3: Cross multiply
    79.70x = 109.76 × 64.14
  4. Step 4: Simplify right side
    79.70x = 7,040.01
  5. Step 5: Solve for x
    x = 7,040.01/79.70
  6. Step 6: Final answer
    x = 88.33

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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.