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Finding the Fourth Proportional to 421.70, 632.60 and 205.13

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Solution

The fourth proportional to 421.70, 632.60 and 205.13 is: 307.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.70 : 632.60 = 205.13 : x
  2. Step 2: Convert to fraction form
    421.70/632.60 = 205.13/x
  3. Step 3: Cross multiply
    421.70x = 632.60 × 205.13
  4. Step 4: Simplify right side
    421.70x = 129,765.24
  5. Step 5: Solve for x
    x = 129,765.24/421.70
  6. Step 6: Final answer
    x = 307.72

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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.