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Finding the Fourth Proportional to 78.14, 107.80 and 49.02

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Solution

The fourth proportional to 78.14, 107.80 and 49.02 is: 67.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.14 : 107.80 = 49.02 : x
  2. Step 2: Convert to fraction form
    78.14/107.80 = 49.02/x
  3. Step 3: Cross multiply
    78.14x = 107.80 × 49.02
  4. Step 4: Simplify right side
    78.14x = 5,284.36
  5. Step 5: Solve for x
    x = 5,284.36/78.14
  6. Step 6: Final answer
    x = 67.63

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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.