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Finding the Fourth Proportional to 66.07, 91.19 and 40.20

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Solution

The fourth proportional to 66.07, 91.19 and 40.20 is: 55.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.07 : 91.19 = 40.20 : x
  2. Step 2: Convert to fraction form
    66.07/91.19 = 40.20/x
  3. Step 3: Cross multiply
    66.07x = 91.19 × 40.20
  4. Step 4: Simplify right side
    66.07x = 3,665.84
  5. Step 5: Solve for x
    x = 3,665.84/66.07
  6. Step 6: Final answer
    x = 55.48

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.