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Finding the Fourth Proportional to 2,872, 4,308 and 820

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Solution

The fourth proportional to 2,872, 4,308 and 820 is: 1,230

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,872 : 4,308 = 820 : x
  2. Step 2: Convert to fraction form
    2,872/4,308 = 820/x
  3. Step 3: Cross multiply
    2,872x = 4,308 × 820
  4. Step 4: Simplify right side
    2,872x = 3,532,560
  5. Step 5: Solve for x
    x = 3,532,560/2,872
  6. Step 6: Final answer
    x = 1,230

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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.