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Finding the Fourth Proportional to 155.10, 213.71 and 105.90

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Solution

The fourth proportional to 155.10, 213.71 and 105.90 is: 145.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.10 : 213.71 = 105.90 : x
  2. Step 2: Convert to fraction form
    155.10/213.71 = 105.90/x
  3. Step 3: Cross multiply
    155.10x = 213.71 × 105.90
  4. Step 4: Simplify right side
    155.10x = 22,631.89
  5. Step 5: Solve for x
    x = 22,631.89/155.10
  6. Step 6: Final answer
    x = 145.92

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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.