Home / 7,142.78-9,857.49-3,999.20

Finding the Fourth Proportional to 7,142.78, 9,857.49 and 3,999.20

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Solution

The fourth proportional to 7,142.78, 9,857.49 and 3,999.20 is: 5,519.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    7,142.78 : 9,857.49 = 3,999.20 : x
  2. Step 2: Convert to fraction form
    7,142.78/9,857.49 = 3,999.20/x
  3. Step 3: Cross multiply
    7,142.78x = 9,857.49 × 3,999.20
  4. Step 4: Simplify right side
    7,142.78x = 39,422,074.01
  5. Step 5: Solve for x
    x = 39,422,074.01/7,142.78
  6. Step 6: Final answer
    x = 5,519.15

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.