Home / 1,221.09-1,831.08-387.91

Finding the Fourth Proportional to 1,221.09, 1,831.08 and 387.91

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Solution

The fourth proportional to 1,221.09, 1,831.08 and 387.91 is: 581.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.09 : 1,831.08 = 387.91 : x
  2. Step 2: Convert to fraction form
    1,221.09/1,831.08 = 387.91/x
  3. Step 3: Cross multiply
    1,221.09x = 1,831.08 × 387.91
  4. Step 4: Simplify right side
    1,221.09x = 710,292.30
  5. Step 5: Solve for x
    x = 710,292.30/1,221.09
  6. Step 6: Final answer
    x = 581.69

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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.