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Finding the Fourth Proportional to 82.80, 123.63 and 79.95

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Solution

The fourth proportional to 82.80, 123.63 and 79.95 is: 119.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.80 : 123.63 = 79.95 : x
  2. Step 2: Convert to fraction form
    82.80/123.63 = 79.95/x
  3. Step 3: Cross multiply
    82.80x = 123.63 × 79.95
  4. Step 4: Simplify right side
    82.80x = 9,884.22
  5. Step 5: Solve for x
    x = 9,884.22/82.80
  6. Step 6: Final answer
    x = 119.37

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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.