Home / 21,288.55-31,931.74-8,139.91

Finding the Fourth Proportional to 21,288.55, 31,931.74 and 8,139.91

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Solution

The fourth proportional to 21,288.55, 31,931.74 and 8,139.91 is: 12,209.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,288.55 : 31,931.74 = 8,139.91 : x
  2. Step 2: Convert to fraction form
    21,288.55/31,931.74 = 8,139.91/x
  3. Step 3: Cross multiply
    21,288.55x = 31,931.74 × 8,139.91
  4. Step 4: Simplify right side
    21,288.55x = 259,921,489.74
  5. Step 5: Solve for x
    x = 259,921,489.74/21,288.55
  6. Step 6: Final answer
    x = 12,209.45

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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.