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Finding the Fourth Proportional to 78.81, 118.21 and 46.51

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Solution

The fourth proportional to 78.81, 118.21 and 46.51 is: 69.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.81 : 118.21 = 46.51 : x
  2. Step 2: Convert to fraction form
    78.81/118.21 = 46.51/x
  3. Step 3: Cross multiply
    78.81x = 118.21 × 46.51
  4. Step 4: Simplify right side
    78.81x = 5,498.00
  5. Step 5: Solve for x
    x = 5,498.00/78.81
  6. Step 6: Final answer
    x = 69.77

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.