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Finding the Fourth Proportional to 407.26, 611.25 and 212.40

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Solution

The fourth proportional to 407.26, 611.25 and 212.40 is: 318.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    407.26 : 611.25 = 212.40 : x
  2. Step 2: Convert to fraction form
    407.26/611.25 = 212.40/x
  3. Step 3: Cross multiply
    407.26x = 611.25 × 212.40
  4. Step 4: Simplify right side
    407.26x = 129,829.50
  5. Step 5: Solve for x
    x = 129,829.50/407.26
  6. Step 6: Final answer
    x = 318.79

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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.