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Finding the Fourth Proportional to 211.47, 317.27 and 108.78

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Solution

The fourth proportional to 211.47, 317.27 and 108.78 is: 163.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    211.47 : 317.27 = 108.78 : x
  2. Step 2: Convert to fraction form
    211.47/317.27 = 108.78/x
  3. Step 3: Cross multiply
    211.47x = 317.27 × 108.78
  4. Step 4: Simplify right side
    211.47x = 34,512.63
  5. Step 5: Solve for x
    x = 34,512.63/211.47
  6. Step 6: Final answer
    x = 163.20

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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.