Home / 1,243.43-1,865.13-421.70

Finding the Fourth Proportional to 1,243.43, 1,865.13 and 421.70

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Solution

The fourth proportional to 1,243.43, 1,865.13 and 421.70 is: 632.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,243.43 : 1,865.13 = 421.70 : x
  2. Step 2: Convert to fraction form
    1,243.43/1,865.13 = 421.70/x
  3. Step 3: Cross multiply
    1,243.43x = 1,865.13 × 421.70
  4. Step 4: Simplify right side
    1,243.43x = 786,516.00
  5. Step 5: Solve for x
    x = 786,516.00/1,243.43
  6. Step 6: Final answer
    x = 632.54

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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.