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Finding the Fourth Proportional to 100.81, 151.21 and 39.93

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Solution

The fourth proportional to 100.81, 151.21 and 39.93 is: 59.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    100.81 : 151.21 = 39.93 : x
  2. Step 2: Convert to fraction form
    100.81/151.21 = 39.93/x
  3. Step 3: Cross multiply
    100.81x = 151.21 × 39.93
  4. Step 4: Simplify right side
    100.81x = 6,037.19
  5. Step 5: Solve for x
    x = 6,037.19/100.81
  6. Step 6: Final answer
    x = 59.89

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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.