Home / 21,138.40-31,709.70-7,814.89

Finding the Fourth Proportional to 21,138.40, 31,709.70 and 7,814.89

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Solution

The fourth proportional to 21,138.40, 31,709.70 and 7,814.89 is: 11,723.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,138.40 : 31,709.70 = 7,814.89 : x
  2. Step 2: Convert to fraction form
    21,138.40/31,709.70 = 7,814.89/x
  3. Step 3: Cross multiply
    21,138.40x = 31,709.70 × 7,814.89
  4. Step 4: Simplify right side
    21,138.40x = 247,807,857.07
  5. Step 5: Solve for x
    x = 247,807,857.07/21,138.40
  6. Step 6: Final answer
    x = 11,723.11

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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.