Home / 1,221.13-1,831.98-399.40

Finding the Fourth Proportional to 1,221.13, 1,831.98 and 399.40

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Solution

The fourth proportional to 1,221.13, 1,831.98 and 399.40 is: 599.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.13 : 1,831.98 = 399.40 : x
  2. Step 2: Convert to fraction form
    1,221.13/1,831.98 = 399.40/x
  3. Step 3: Cross multiply
    1,221.13x = 1,831.98 × 399.40
  4. Step 4: Simplify right side
    1,221.13x = 731,687.23
  5. Step 5: Solve for x
    x = 731,687.23/1,221.13
  6. Step 6: Final answer
    x = 599.19

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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.