Home / 1,243.19-1,865.19-421.54

Finding the Fourth Proportional to 1,243.19, 1,865.19 and 421.54

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Solution

The fourth proportional to 1,243.19, 1,865.19 and 421.54 is: 632.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,243.19 : 1,865.19 = 421.54 : x
  2. Step 2: Convert to fraction form
    1,243.19/1,865.19 = 421.54/x
  3. Step 3: Cross multiply
    1,243.19x = 1,865.19 × 421.54
  4. Step 4: Simplify right side
    1,243.19x = 786,252.19
  5. Step 5: Solve for x
    x = 786,252.19/1,243.19
  6. Step 6: Final answer
    x = 632.45

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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.