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Finding the Fourth Proportional to 82.96, 123.70 and 79.78

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Solution

The fourth proportional to 82.96, 123.70 and 79.78 is: 118.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.96 : 123.70 = 79.78 : x
  2. Step 2: Convert to fraction form
    82.96/123.70 = 79.78/x
  3. Step 3: Cross multiply
    82.96x = 123.70 × 79.78
  4. Step 4: Simplify right side
    82.96x = 9,868.79
  5. Step 5: Solve for x
    x = 9,868.79/82.96
  6. Step 6: Final answer
    x = 118.96

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.