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Finding the Fourth Proportional to 149.31, 206.40 and 135.81

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Solution

The fourth proportional to 149.31, 206.40 and 135.81 is: 187.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    149.31 : 206.40 = 135.81 : x
  2. Step 2: Convert to fraction form
    149.31/206.40 = 135.81/x
  3. Step 3: Cross multiply
    149.31x = 206.40 × 135.81
  4. Step 4: Simplify right side
    149.31x = 28,031.18
  5. Step 5: Solve for x
    x = 28,031.18/149.31
  6. Step 6: Final answer
    x = 187.74

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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.