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Finding the Fourth Proportional to 280.43, 386.57 and 197.40

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Solution

The fourth proportional to 280.43, 386.57 and 197.40 is: 272.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.43 : 386.57 = 197.40 : x
  2. Step 2: Convert to fraction form
    280.43/386.57 = 197.40/x
  3. Step 3: Cross multiply
    280.43x = 386.57 × 197.40
  4. Step 4: Simplify right side
    280.43x = 76,307.93
  5. Step 5: Solve for x
    x = 76,307.93/280.43
  6. Step 6: Final answer
    x = 272.12

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.