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Finding the Fourth Proportional to 218.90, 326.15 and 213.10

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Solution

The fourth proportional to 218.90, 326.15 and 213.10 is: 317.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.90 : 326.15 = 213.10 : x
  2. Step 2: Convert to fraction form
    218.90/326.15 = 213.10/x
  3. Step 3: Cross multiply
    218.90x = 326.15 × 213.10
  4. Step 4: Simplify right side
    218.90x = 69,502.57
  5. Step 5: Solve for x
    x = 69,502.57/218.90
  6. Step 6: Final answer
    x = 317.51

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.