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Finding the Fourth Proportional to 215.90, 323.71 and 78.93

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Solution

The fourth proportional to 215.90, 323.71 and 78.93 is: 118.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    215.90 : 323.71 = 78.93 : x
  2. Step 2: Convert to fraction form
    215.90/323.71 = 78.93/x
  3. Step 3: Cross multiply
    215.90x = 323.71 × 78.93
  4. Step 4: Simplify right side
    215.90x = 25,550.23
  5. Step 5: Solve for x
    x = 25,550.23/215.90
  6. Step 6: Final answer
    x = 118.34

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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.