Home / 1,287.04-1,930.86-421.96

Finding the Fourth Proportional to 1,287.04, 1,930.86 and 421.96

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Solution

The fourth proportional to 1,287.04, 1,930.86 and 421.96 is: 633.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.04 : 1,930.86 = 421.96 : x
  2. Step 2: Convert to fraction form
    1,287.04/1,930.86 = 421.96/x
  3. Step 3: Cross multiply
    1,287.04x = 1,930.86 × 421.96
  4. Step 4: Simplify right side
    1,287.04x = 814,745.69
  5. Step 5: Solve for x
    x = 814,745.69/1,287.04
  6. Step 6: Final answer
    x = 633.04

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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.