Home / 1,987.13-2,741.46-1,389.47

Finding the Fourth Proportional to 1,987.13, 2,741.46 and 1,389.47

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Solution

The fourth proportional to 1,987.13, 2,741.46 and 1,389.47 is: 1,916.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.13 : 2,741.46 = 1,389.47 : x
  2. Step 2: Convert to fraction form
    1,987.13/2,741.46 = 1,389.47/x
  3. Step 3: Cross multiply
    1,987.13x = 2,741.46 × 1,389.47
  4. Step 4: Simplify right side
    1,987.13x = 3,809,162.72
  5. Step 5: Solve for x
    x = 3,809,162.72/1,987.13
  6. Step 6: Final answer
    x = 1,916.92

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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.