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Finding the Fourth Proportional to 410.70, 615.90 and 136.80

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Solution

The fourth proportional to 410.70, 615.90 and 136.80 is: 205.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.70 : 615.90 = 136.80 : x
  2. Step 2: Convert to fraction form
    410.70/615.90 = 136.80/x
  3. Step 3: Cross multiply
    410.70x = 615.90 × 136.80
  4. Step 4: Simplify right side
    410.70x = 84,255.12
  5. Step 5: Solve for x
    x = 84,255.12/410.70
  6. Step 6: Final answer
    x = 205.15

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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.