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Finding the Fourth Proportional to 218.70, 307.80 and 218.70

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Solution

The fourth proportional to 218.70, 307.80 and 218.70 is: 307.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    218.70 : 307.80 = 218.70 : x
  2. Step 2: Convert to fraction form
    218.70/307.80 = 218.70/x
  3. Step 3: Cross multiply
    218.70x = 307.80 × 218.70
  4. Step 4: Simplify right side
    218.70x = 67,315.86
  5. Step 5: Solve for x
    x = 67,315.86/218.70
  6. Step 6: Final answer
    x = 307.80

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Why These Related Problems?

These problems maintain the same ratio (1.41) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.