Home / 1,221.40-1,831.90-355.51

Finding the Fourth Proportional to 1,221.40, 1,831.90 and 355.51

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Solution

The fourth proportional to 1,221.40, 1,831.90 and 355.51 is: 533.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.40 : 1,831.90 = 355.51 : x
  2. Step 2: Convert to fraction form
    1,221.40/1,831.90 = 355.51/x
  3. Step 3: Cross multiply
    1,221.40x = 1,831.90 × 355.51
  4. Step 4: Simplify right side
    1,221.40x = 651,256.99
  5. Step 5: Solve for x
    x = 651,256.99/1,221.40
  6. Step 6: Final answer
    x = 533.21

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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.