Home / 21,145.78-31,685.70-7,990.96

Finding the Fourth Proportional to 21,145.78, 31,685.70 and 7,990.96

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Solution

The fourth proportional to 21,145.78, 31,685.70 and 7,990.96 is: 11,973.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,145.78 : 31,685.70 = 7,990.96 : x
  2. Step 2: Convert to fraction form
    21,145.78/31,685.70 = 7,990.96/x
  3. Step 3: Cross multiply
    21,145.78x = 31,685.70 × 7,990.96
  4. Step 4: Simplify right side
    21,145.78x = 253,199,161.27
  5. Step 5: Solve for x
    x = 253,199,161.27/21,145.78
  6. Step 6: Final answer
    x = 11,973.98

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1.5x scale

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.