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Finding the Fourth Proportional to 1,872.32, 2,808.63 and 639.81

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Solution

The fourth proportional to 1,872.32, 2,808.63 and 639.81 is: 959.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,872.32 : 2,808.63 = 639.81 : x
  2. Step 2: Convert to fraction form
    1,872.32/2,808.63 = 639.81/x
  3. Step 3: Cross multiply
    1,872.32x = 2,808.63 × 639.81
  4. Step 4: Simplify right side
    1,872.32x = 1,796,989.56
  5. Step 5: Solve for x
    x = 1,796,989.56/1,872.32
  6. Step 6: Final answer
    x = 959.77

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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.