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Finding the Fourth Proportional to 76.40, 105.63 and 57.95

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Solution

The fourth proportional to 76.40, 105.63 and 57.95 is: 80.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    76.40 : 105.63 = 57.95 : x
  2. Step 2: Convert to fraction form
    76.40/105.63 = 57.95/x
  3. Step 3: Cross multiply
    76.40x = 105.63 × 57.95
  4. Step 4: Simplify right side
    76.40x = 6,120.91
  5. Step 5: Solve for x
    x = 6,120.91/76.40
  6. Step 6: Final answer
    x = 80.12

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.