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Finding the Fourth Proportional to 410.78, 615.70 and 205.14

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Solution

The fourth proportional to 410.78, 615.70 and 205.14 is: 307.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.78 : 615.70 = 205.14 : x
  2. Step 2: Convert to fraction form
    410.78/615.70 = 205.14/x
  3. Step 3: Cross multiply
    410.78x = 615.70 × 205.14
  4. Step 4: Simplify right side
    410.78x = 126,304.19
  5. Step 5: Solve for x
    x = 126,304.19/410.78
  6. Step 6: Final answer
    x = 307.48

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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.