Home / 1,220.78-1,831.31-399.08

Finding the Fourth Proportional to 1,220.78, 1,831.31 and 399.08

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Solution

The fourth proportional to 1,220.78, 1,831.31 and 399.08 is: 598.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,220.78 : 1,831.31 = 399.08 : x
  2. Step 2: Convert to fraction form
    1,220.78/1,831.31 = 399.08/x
  3. Step 3: Cross multiply
    1,220.78x = 1,831.31 × 399.08
  4. Step 4: Simplify right side
    1,220.78x = 730,828.04
  5. Step 5: Solve for x
    x = 730,828.04/1,220.78
  6. Step 6: Final answer
    x = 598.66

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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.