Home / 1,220.80-1,831.52-399.20

Finding the Fourth Proportional to 1,220.80, 1,831.52 and 399.20

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Solution

The fourth proportional to 1,220.80, 1,831.52 and 399.20 is: 598.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.80 : 1,831.52 = 399.20 : x
  2. Step 2: Convert to fraction form
    1,220.80/1,831.52 = 399.20/x
  3. Step 3: Cross multiply
    1,220.80x = 1,831.52 × 399.20
  4. Step 4: Simplify right side
    1,220.80x = 731,142.78
  5. Step 5: Solve for x
    x = 731,142.78/1,220.80
  6. Step 6: Final answer
    x = 598.90

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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.