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Finding the Fourth Proportional to 79.80, 119.28 and 55.80

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Solution

The fourth proportional to 79.80, 119.28 and 55.80 is: 83.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    79.80 : 119.28 = 55.80 : x
  2. Step 2: Convert to fraction form
    79.80/119.28 = 55.80/x
  3. Step 3: Cross multiply
    79.80x = 119.28 × 55.80
  4. Step 4: Simplify right side
    79.80x = 6,655.82
  5. Step 5: Solve for x
    x = 6,655.82/79.80
  6. Step 6: Final answer
    x = 83.41

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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.