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Finding the Fourth Proportional to 66.12, 98.91 and 45.78

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Solution

The fourth proportional to 66.12, 98.91 and 45.78 is: 68.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.12 : 98.91 = 45.78 : x
  2. Step 2: Convert to fraction form
    66.12/98.91 = 45.78/x
  3. Step 3: Cross multiply
    66.12x = 98.91 × 45.78
  4. Step 4: Simplify right side
    66.12x = 4,528.10
  5. Step 5: Solve for x
    x = 4,528.10/66.12
  6. Step 6: Final answer
    x = 68.48

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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.