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Finding the Fourth Proportional to 1,871.71, 2,808.02 and 638.79

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Solution

The fourth proportional to 1,871.71, 2,808.02 and 638.79 is: 958.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,871.71 : 2,808.02 = 638.79 : x
  2. Step 2: Convert to fraction form
    1,871.71/2,808.02 = 638.79/x
  3. Step 3: Cross multiply
    1,871.71x = 2,808.02 × 638.79
  4. Step 4: Simplify right side
    1,871.71x = 1,793,722.57
  5. Step 5: Solve for x
    x = 1,793,722.57/1,871.71
  6. Step 6: Final answer
    x = 958.33

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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.