Home / 1,221.31-1,831.87-490.38

Finding the Fourth Proportional to 1,221.31, 1,831.87 and 490.38

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Solution

The fourth proportional to 1,221.31, 1,831.87 and 490.38 is: 735.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.31 : 1,831.87 = 490.38 : x
  2. Step 2: Convert to fraction form
    1,221.31/1,831.87 = 490.38/x
  3. Step 3: Cross multiply
    1,221.31x = 1,831.87 × 490.38
  4. Step 4: Simplify right side
    1,221.31x = 898,312.41
  5. Step 5: Solve for x
    x = 898,312.41/1,221.31
  6. Step 6: Final answer
    x = 735.53

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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.