Home / 1,279.60-1,921-1,220.76

Finding the Fourth Proportional to 1,279.60, 1,921 and 1,220.76

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Solution

The fourth proportional to 1,279.60, 1,921 and 1,220.76 is: 1,832.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,279.60 : 1,921 = 1,220.76 : x
  2. Step 2: Convert to fraction form
    1,279.60/1,921 = 1,220.76/x
  3. Step 3: Cross multiply
    1,279.60x = 1,921 × 1,220.76
  4. Step 4: Simplify right side
    1,279.60x = 2,345,079.96
  5. Step 5: Solve for x
    x = 2,345,079.96/1,279.60
  6. Step 6: Final answer
    x = 1,832.67

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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.