Home / 1,221.28-1,831.54-399.38

Finding the Fourth Proportional to 1,221.28, 1,831.54 and 399.38

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Solution

The fourth proportional to 1,221.28, 1,831.54 and 399.38 is: 598.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.28 : 1,831.54 = 399.38 : x
  2. Step 2: Convert to fraction form
    1,221.28/1,831.54 = 399.38/x
  3. Step 3: Cross multiply
    1,221.28x = 1,831.54 × 399.38
  4. Step 4: Simplify right side
    1,221.28x = 731,480.45
  5. Step 5: Solve for x
    x = 731,480.45/1,221.28
  6. Step 6: Final answer
    x = 598.95

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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.