Home / 1,987.75-2,742.15-1,398.61

Finding the Fourth Proportional to 1,987.75, 2,742.15 and 1,398.61

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Solution

The fourth proportional to 1,987.75, 2,742.15 and 1,398.61 is: 1,929.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.75 : 2,742.15 = 1,398.61 : x
  2. Step 2: Convert to fraction form
    1,987.75/2,742.15 = 1,398.61/x
  3. Step 3: Cross multiply
    1,987.75x = 2,742.15 × 1,398.61
  4. Step 4: Simplify right side
    1,987.75x = 3,835,198.41
  5. Step 5: Solve for x
    x = 3,835,198.41/1,987.75
  6. Step 6: Final answer
    x = 1,929.42

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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.