Home / 3,987.80-5,979.98-1,318.64

Finding the Fourth Proportional to 3,987.80, 5,979.98 and 1,318.64

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Solution

The fourth proportional to 3,987.80, 5,979.98 and 1,318.64 is: 1,977.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,987.80 : 5,979.98 = 1,318.64 : x
  2. Step 2: Convert to fraction form
    3,987.80/5,979.98 = 1,318.64/x
  3. Step 3: Cross multiply
    3,987.80x = 5,979.98 × 1,318.64
  4. Step 4: Simplify right side
    3,987.80x = 7,885,440.83
  5. Step 5: Solve for x
    x = 7,885,440.83/3,987.80
  6. Step 6: Final answer
    x = 1,977.39

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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.