Home / 1,221.20-1,831.80-441.20

Finding the Fourth Proportional to 1,221.20, 1,831.80 and 441.20

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Solution

The fourth proportional to 1,221.20, 1,831.80 and 441.20 is: 661.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.20 : 1,831.80 = 441.20 : x
  2. Step 2: Convert to fraction form
    1,221.20/1,831.80 = 441.20/x
  3. Step 3: Cross multiply
    1,221.20x = 1,831.80 × 441.20
  4. Step 4: Simplify right side
    1,221.20x = 808,190.16
  5. Step 5: Solve for x
    x = 808,190.16/1,221.20
  6. Step 6: Final answer
    x = 661.80

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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.