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Finding the Fourth Proportional to 82.04, 123.57 and 77.78

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Solution

The fourth proportional to 82.04, 123.57 and 77.78 is: 117.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    82.04 : 123.57 = 77.78 : x
  2. Step 2: Convert to fraction form
    82.04/123.57 = 77.78/x
  3. Step 3: Cross multiply
    82.04x = 123.57 × 77.78
  4. Step 4: Simplify right side
    82.04x = 9,611.58
  5. Step 5: Solve for x
    x = 9,611.58/82.04
  6. Step 6: Final answer
    x = 117.16

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.