Home / 1,391.13-2,087.08-611.21

Finding the Fourth Proportional to 1,391.13, 2,087.08 and 611.21

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Solution

The fourth proportional to 1,391.13, 2,087.08 and 611.21 is: 916.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.13 : 2,087.08 = 611.21 : x
  2. Step 2: Convert to fraction form
    1,391.13/2,087.08 = 611.21/x
  3. Step 3: Cross multiply
    1,391.13x = 2,087.08 × 611.21
  4. Step 4: Simplify right side
    1,391.13x = 1,275,632.20
  5. Step 5: Solve for x
    x = 1,275,632.20/1,391.13
  6. Step 6: Final answer
    x = 916.98

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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.