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Finding the Fourth Proportional to 66.10, 91.19 and 42.81

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Solution

The fourth proportional to 66.10, 91.19 and 42.81 is: 59.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.10 : 91.19 = 42.81 : x
  2. Step 2: Convert to fraction form
    66.10/91.19 = 42.81/x
  3. Step 3: Cross multiply
    66.10x = 91.19 × 42.81
  4. Step 4: Simplify right side
    66.10x = 3,903.84
  5. Step 5: Solve for x
    x = 3,903.84/66.10
  6. Step 6: Final answer
    x = 59.06

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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.