Home / 1,311.85-1,968.12-387.43

Finding the Fourth Proportional to 1,311.85, 1,968.12 and 387.43

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Solution

The fourth proportional to 1,311.85, 1,968.12 and 387.43 is: 581.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,311.85 : 1,968.12 = 387.43 : x
  2. Step 2: Convert to fraction form
    1,311.85/1,968.12 = 387.43/x
  3. Step 3: Cross multiply
    1,311.85x = 1,968.12 × 387.43
  4. Step 4: Simplify right side
    1,311.85x = 762,508.73
  5. Step 5: Solve for x
    x = 762,508.73/1,311.85
  6. Step 6: Final answer
    x = 581.25

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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.