Home / 1,987.28-2,979.35-1,255.31

Finding the Fourth Proportional to 1,987.28, 2,979.35 and 1,255.31

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Solution

The fourth proportional to 1,987.28, 2,979.35 and 1,255.31 is: 1,881.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.28 : 2,979.35 = 1,255.31 : x
  2. Step 2: Convert to fraction form
    1,987.28/2,979.35 = 1,255.31/x
  3. Step 3: Cross multiply
    1,987.28x = 2,979.35 × 1,255.31
  4. Step 4: Simplify right side
    1,987.28x = 3,740,018.44
  5. Step 5: Solve for x
    x = 3,740,018.44/1,987.28
  6. Step 6: Final answer
    x = 1,881.98

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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.