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Finding the Fourth Proportional to 80.88, 111.72 and 70.16

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Solution

The fourth proportional to 80.88, 111.72 and 70.16 is: 96.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.88 : 111.72 = 70.16 : x
  2. Step 2: Convert to fraction form
    80.88/111.72 = 70.16/x
  3. Step 3: Cross multiply
    80.88x = 111.72 × 70.16
  4. Step 4: Simplify right side
    80.88x = 7,838.28
  5. Step 5: Solve for x
    x = 7,838.28/80.88
  6. Step 6: Final answer
    x = 96.91

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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.