Home / 1,213.60-1,820.40-391.93

Finding the Fourth Proportional to 1,213.60, 1,820.40 and 391.93

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Solution

The fourth proportional to 1,213.60, 1,820.40 and 391.93 is: 587.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,213.60 : 1,820.40 = 391.93 : x
  2. Step 2: Convert to fraction form
    1,213.60/1,820.40 = 391.93/x
  3. Step 3: Cross multiply
    1,213.60x = 1,820.40 × 391.93
  4. Step 4: Simplify right side
    1,213.60x = 713,469.37
  5. Step 5: Solve for x
    x = 713,469.37/1,213.60
  6. Step 6: Final answer
    x = 587.90

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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.