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Finding the Fourth Proportional to 410.78, 615.71 and 205.16

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Solution

The fourth proportional to 410.78, 615.71 and 205.16 is: 307.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.78 : 615.71 = 205.16 : x
  2. Step 2: Convert to fraction form
    410.78/615.71 = 205.16/x
  3. Step 3: Cross multiply
    410.78x = 615.71 × 205.16
  4. Step 4: Simplify right side
    410.78x = 126,314.96
  5. Step 5: Solve for x
    x = 126,314.96/410.78
  6. Step 6: Final answer
    x = 307.50

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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.