Home / 21,140.28-31,710.96-7,990.20

Finding the Fourth Proportional to 21,140.28, 31,710.96 and 7,990.20

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Solution

The fourth proportional to 21,140.28, 31,710.96 and 7,990.20 is: 11,985.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    21,140.28 : 31,710.96 = 7,990.20 : x
  2. Step 2: Convert to fraction form
    21,140.28/31,710.96 = 7,990.20/x
  3. Step 3: Cross multiply
    21,140.28x = 31,710.96 × 7,990.20
  4. Step 4: Simplify right side
    21,140.28x = 253,376,912.59
  5. Step 5: Solve for x
    x = 253,376,912.59/21,140.28
  6. Step 6: Final answer
    x = 11,985.50

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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.