Home / 1,391.30-2,085.38-611.06

Finding the Fourth Proportional to 1,391.30, 2,085.38 and 611.06

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Solution

The fourth proportional to 1,391.30, 2,085.38 and 611.06 is: 915.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,391.30 : 2,085.38 = 611.06 : x
  2. Step 2: Convert to fraction form
    1,391.30/2,085.38 = 611.06/x
  3. Step 3: Cross multiply
    1,391.30x = 2,085.38 × 611.06
  4. Step 4: Simplify right side
    1,391.30x = 1,274,292.30
  5. Step 5: Solve for x
    x = 1,274,292.30/1,391.30
  6. Step 6: Final answer
    x = 915.90

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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.