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Finding the Fourth Proportional to 78.59, 118.03 and 66.50

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Solution

The fourth proportional to 78.59, 118.03 and 66.50 is: 99.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    78.59 : 118.03 = 66.50 : x
  2. Step 2: Convert to fraction form
    78.59/118.03 = 66.50/x
  3. Step 3: Cross multiply
    78.59x = 118.03 × 66.50
  4. Step 4: Simplify right side
    78.59x = 7,849.12
  5. Step 5: Solve for x
    x = 7,849.12/78.59
  6. Step 6: Final answer
    x = 99.88

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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.