Home / 1,221.38-1,831.80-490.40

Finding the Fourth Proportional to 1,221.38, 1,831.80 and 490.40

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Solution

The fourth proportional to 1,221.38, 1,831.80 and 490.40 is: 735.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.38 : 1,831.80 = 490.40 : x
  2. Step 2: Convert to fraction form
    1,221.38/1,831.80 = 490.40/x
  3. Step 3: Cross multiply
    1,221.38x = 1,831.80 × 490.40
  4. Step 4: Simplify right side
    1,221.38x = 898,314.72
  5. Step 5: Solve for x
    x = 898,314.72/1,221.38
  6. Step 6: Final answer
    x = 735.49

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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.