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Finding the Fourth Proportional to 127.40, 175.61 and 78.19

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Solution

The fourth proportional to 127.40, 175.61 and 78.19 is: 107.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    127.40 : 175.61 = 78.19 : x
  2. Step 2: Convert to fraction form
    127.40/175.61 = 78.19/x
  3. Step 3: Cross multiply
    127.40x = 175.61 × 78.19
  4. Step 4: Simplify right side
    127.40x = 13,730.07
  5. Step 5: Solve for x
    x = 13,730.07/127.40
  6. Step 6: Final answer
    x = 107.78

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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.