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Finding the Fourth Proportional to 66.31, 91.51 and 36.81

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Solution

The fourth proportional to 66.31, 91.51 and 36.81 is: 50.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    66.31 : 91.51 = 36.81 : x
  2. Step 2: Convert to fraction form
    66.31/91.51 = 36.81/x
  3. Step 3: Cross multiply
    66.31x = 91.51 × 36.81
  4. Step 4: Simplify right side
    66.31x = 3,368.35
  5. Step 5: Solve for x
    x = 3,368.35/66.31
  6. Step 6: Final answer
    x = 50.80

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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.