Home / 1,987.81-2,742.97-1,148.78

Finding the Fourth Proportional to 1,987.81, 2,742.97 and 1,148.78

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Solution

The fourth proportional to 1,987.81, 2,742.97 and 1,148.78 is: 1,585.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.81 : 2,742.97 = 1,148.78 : x
  2. Step 2: Convert to fraction form
    1,987.81/2,742.97 = 1,148.78/x
  3. Step 3: Cross multiply
    1,987.81x = 2,742.97 × 1,148.78
  4. Step 4: Simplify right side
    1,987.81x = 3,151,069.08
  5. Step 5: Solve for x
    x = 3,151,069.08/1,987.81
  6. Step 6: Final answer
    x = 1,585.20

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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.