Home / 1,351.40-2,021.70-1,221.80

Finding the Fourth Proportional to 1,351.40, 2,021.70 and 1,221.80

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Solution

The fourth proportional to 1,351.40, 2,021.70 and 1,221.80 is: 1,827.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,351.40 : 2,021.70 = 1,221.80 : x
  2. Step 2: Convert to fraction form
    1,351.40/2,021.70 = 1,221.80/x
  3. Step 3: Cross multiply
    1,351.40x = 2,021.70 × 1,221.80
  4. Step 4: Simplify right side
    1,351.40x = 2,470,113.06
  5. Step 5: Solve for x
    x = 2,470,113.06/1,351.40
  6. Step 6: Final answer
    x = 1,827.82

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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.