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Finding the Fourth Proportional to 218.09, 300.87 and 135.15

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Solution

The fourth proportional to 218.09, 300.87 and 135.15 is: 186.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.09 : 300.87 = 135.15 : x
  2. Step 2: Convert to fraction form
    218.09/300.87 = 135.15/x
  3. Step 3: Cross multiply
    218.09x = 300.87 × 135.15
  4. Step 4: Simplify right side
    218.09x = 40,662.58
  5. Step 5: Solve for x
    x = 40,662.58/218.09
  6. Step 6: Final answer
    x = 186.45

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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.