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Finding the Fourth Proportional to 78.50, 118.21 and 58.35

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Solution

The fourth proportional to 78.50, 118.21 and 58.35 is: 87.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.50 : 118.21 = 58.35 : x
  2. Step 2: Convert to fraction form
    78.50/118.21 = 58.35/x
  3. Step 3: Cross multiply
    78.50x = 118.21 × 58.35
  4. Step 4: Simplify right side
    78.50x = 6,897.96
  5. Step 5: Solve for x
    x = 6,897.96/78.50
  6. Step 6: Final answer
    x = 87.87

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.