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Finding the Fourth Proportional to 71.10, 97.20 and 70.80

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Solution

The fourth proportional to 71.10, 97.20 and 70.80 is: 96.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    71.10 : 97.20 = 70.80 : x
  2. Step 2: Convert to fraction form
    71.10/97.20 = 70.80/x
  3. Step 3: Cross multiply
    71.10x = 97.20 × 70.80
  4. Step 4: Simplify right side
    71.10x = 6,881.76
  5. Step 5: Solve for x
    x = 6,881.76/71.10
  6. Step 6: Final answer
    x = 96.79

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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.