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Finding the Fourth Proportional to 211.28, 317.10 and 103.15

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Solution

The fourth proportional to 211.28, 317.10 and 103.15 is: 154.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    211.28 : 317.10 = 103.15 : x
  2. Step 2: Convert to fraction form
    211.28/317.10 = 103.15/x
  3. Step 3: Cross multiply
    211.28x = 317.10 × 103.15
  4. Step 4: Simplify right side
    211.28x = 32,708.87
  5. Step 5: Solve for x
    x = 32,708.87/211.28
  6. Step 6: Final answer
    x = 154.81

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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.