Home / 1,987.80-2,979.57-1,257.58

Finding the Fourth Proportional to 1,987.80, 2,979.57 and 1,257.58

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Solution

The fourth proportional to 1,987.80, 2,979.57 and 1,257.58 is: 1,885.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.80 : 2,979.57 = 1,257.58 : x
  2. Step 2: Convert to fraction form
    1,987.80/2,979.57 = 1,257.58/x
  3. Step 3: Cross multiply
    1,987.80x = 2,979.57 × 1,257.58
  4. Step 4: Simplify right side
    1,987.80x = 3,747,047.64
  5. Step 5: Solve for x
    x = 3,747,047.64/1,987.80
  6. Step 6: Final answer
    x = 1,885.02

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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.