Home / 3,989.78-5,505.80-2,221.35

Finding the Fourth Proportional to 3,989.78, 5,505.80 and 2,221.35

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Solution

The fourth proportional to 3,989.78, 5,505.80 and 2,221.35 is: 3,065.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,989.78 : 5,505.80 = 2,221.35 : x
  2. Step 2: Convert to fraction form
    3,989.78/5,505.80 = 2,221.35/x
  3. Step 3: Cross multiply
    3,989.78x = 5,505.80 × 2,221.35
  4. Step 4: Simplify right side
    3,989.78x = 12,230,314.38
  5. Step 5: Solve for x
    x = 12,230,314.38/3,989.78
  6. Step 6: Final answer
    x = 3,065.41

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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.