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Finding the Fourth Proportional to 2,865, 3,953.70 and 1,686.80

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Solution

The fourth proportional to 2,865, 3,953.70 and 1,686.80 is: 2,327.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    2,865 : 3,953.70 = 1,686.80 : x
  2. Step 2: Convert to fraction form
    2,865/3,953.70 = 1,686.80/x
  3. Step 3: Cross multiply
    2,865x = 3,953.70 × 1,686.80
  4. Step 4: Simplify right side
    2,865x = 6,669,081.39
  5. Step 5: Solve for x
    x = 6,669,081.39/2,865
  6. Step 6: Final answer
    x = 2,327.78

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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.