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Finding the Fourth Proportional to 155.30, 215.38 and 153.47

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Solution

The fourth proportional to 155.30, 215.38 and 153.47 is: 212.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    155.30 : 215.38 = 153.47 : x
  2. Step 2: Convert to fraction form
    155.30/215.38 = 153.47/x
  3. Step 3: Cross multiply
    155.30x = 215.38 × 153.47
  4. Step 4: Simplify right side
    155.30x = 33,055.10
  5. Step 5: Solve for x
    x = 33,055.10/155.30
  6. Step 6: Final answer
    x = 212.85

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.