Home / 3,928-5,420.70-2,159.68

Finding the Fourth Proportional to 3,928, 5,420.70 and 2,159.68

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Solution

The fourth proportional to 3,928, 5,420.70 and 2,159.68 is: 2,980.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,928 : 5,420.70 = 2,159.68 : x
  2. Step 2: Convert to fraction form
    3,928/5,420.70 = 2,159.68/x
  3. Step 3: Cross multiply
    3,928x = 5,420.70 × 2,159.68
  4. Step 4: Simplify right side
    3,928x = 11,706,977.38
  5. Step 5: Solve for x
    x = 11,706,977.38/3,928
  6. Step 6: Final answer
    x = 2,980.39

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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.